After breakfast this morning I spent a little time working on my powerpoint and making a few changes that my advisor recommended. If you'd like to see it, click here (~7.5 MB).
From there it was back to the lab to reduce more images. I'm finished with the two images taken in the blue filter, so now it's on to the I band, which is in the infrared. When first diplaying the image I expected that it wouldn't work out well because there seems to be a lot of strange noise.
Surprisingly, it seems that it ended up coming out better than the B images. I ended up getting through three images today, out of nine total, so that leaves me with 4 left. Hopefully, I'll be finished with this stage of processing by Monday and can move onto something new.
Tomorrow I'll probably spend the morning processing another image or two, and then the afternoon before my presentation rehearsing.
Friday, June 30, 2006
Thursday, June 29, 2006
Faith Based Failure
After Republicans failed to pass a law giving money to religious organizations for charitable purposes, President Bush passed it anyway by means of an executive order, terming them "Faith Based Initiatives".
The justification for such initiatives is that religious organizations are able to do charitable works better than secular ones. Why? I haven't a clue as there's never been any evidence I've seen supporting this. But given that many seem to think that churches have some moral high ground and are inherently better than any secular organization.
But it seems that at least one church recieving such a grant to aid those affected by Hurricane Katrina, is under heavy fire as one of its priests has been accused of raping a woman. So much for moral superiority.
Furthermore, the church, run in a strip mall, faces eviction for failure to pay their rent. This should speak volumes about thier money management skills that should have been considered before the federal government forked over $43,534 to them.
But who knows. Perhaps they really are a good charitable organization and don't have money to pay their rent because they were spending it all on the needey.
Or not.
Instead of helping the homeless with charity, the church charged homeless $3-5 to spend the night. They are being served with a code violation for failure to have a liscence to run a hotel.
So it would seem that $43,534 of taxpayer's money has disappeared to a shady church. But I'm sure this is an isolated incident. After all, the government would never hand over millions to money grubbing mega churches like the ones run by Pat Robertson.
Oh wait. Yeah they did.
The justification for such initiatives is that religious organizations are able to do charitable works better than secular ones. Why? I haven't a clue as there's never been any evidence I've seen supporting this. But given that many seem to think that churches have some moral high ground and are inherently better than any secular organization.
But it seems that at least one church recieving such a grant to aid those affected by Hurricane Katrina, is under heavy fire as one of its priests has been accused of raping a woman. So much for moral superiority.
Furthermore, the church, run in a strip mall, faces eviction for failure to pay their rent. This should speak volumes about thier money management skills that should have been considered before the federal government forked over $43,534 to them.
But who knows. Perhaps they really are a good charitable organization and don't have money to pay their rent because they were spending it all on the needey.
Or not.
Instead of helping the homeless with charity, the church charged homeless $3-5 to spend the night. They are being served with a code violation for failure to have a liscence to run a hotel.
So it would seem that $43,534 of taxpayer's money has disappeared to a shady church. But I'm sure this is an isolated incident. After all, the government would never hand over millions to money grubbing mega churches like the ones run by Pat Robertson.
Oh wait. Yeah they did.
The 'Miracle' of Near Death Experiences
I've seen this article popping up on quite a few religious news sites recently and have been amazed at the terrible scholarship and shoddy conclusions those of religious persuasion have been applying to this study.
The study investigates near death experiences and seeks to identify what experiences are common amongst them. The most common was that those who had such experiences felt like they had risen from their bodies and seen a bright light.
Also noted was the religious affiliation of those surveyed. OF them, 54% were from the Church of England, 12% Catholic, 19% other Christian, 1% Jewish, 8% agnostic, and 2% atheist. This corresponds with the percentage of the population of each faith indicating that any person is equally likely to have such experiences, regardless of faith.
There are a few other interesting tidbits in there, but nothing else that I feel needs to be commented on at this point.
However, what I have noticed is that the article portrays such experiences as legitimate, religious experiences, yet have chosen to ignore the scientific justification for them. Similar experiences and hallucinations are frequently reported as a result of oxygen deprevation, especially the characteristic bright tunnel.
The article goes even further, quoting a Dr. making extremely unscientific conclusions:
The only one that seems to fit in any manner is the "you are not yoru body" conclusion. However, in light of the studies showing that such experiences are not a result of some metaphyical realm, but instead simply of natural effects, this statement is directly contradicted.
However, if you're going to ignore such things and are really interested in drawing conclusions from this, here's a few that I'd recommend:
-- Since religious affiliation doesn't play a role in getting to such a paradise, it proves that all religions are equally wrong.
-- There is a life after death so why bother doing anything worhtwhile in this one?
-- The article mentions that injuries in the afterlife are miraculously healed, so why not go chop someone's arm off?
If you haven't caught the sarcasm, let me take this opporunity to point out that each of those was sarcastic and, when viewed in light of the complete body of evidence, cannot stand. However, I doubt any amount of evidence would convice those that what they saw wasn't real. I've not had such an experience, so I suppose I have no room to pass judgement. Nor do I have room to pass judgement on people that have been abducted by aliens, or seen bigfoot, etc...
The study investigates near death experiences and seeks to identify what experiences are common amongst them. The most common was that those who had such experiences felt like they had risen from their bodies and seen a bright light.
Also noted was the religious affiliation of those surveyed. OF them, 54% were from the Church of England, 12% Catholic, 19% other Christian, 1% Jewish, 8% agnostic, and 2% atheist. This corresponds with the percentage of the population of each faith indicating that any person is equally likely to have such experiences, regardless of faith.
There are a few other interesting tidbits in there, but nothing else that I feel needs to be commented on at this point.
However, what I have noticed is that the article portrays such experiences as legitimate, religious experiences, yet have chosen to ignore the scientific justification for them. Similar experiences and hallucinations are frequently reported as a result of oxygen deprevation, especially the characteristic bright tunnel.
The article goes even further, quoting a Dr. making extremely unscientific conclusions:
According to a second prominent researcher, Dr. Kenneth Ring of Connecticut, the main lessons learned from such experiences can be synopsized as follows:I find no way that many of these are related to the research in any manner. Instead, most are vauge philosophical statements tossed in as an attempt to give them some sort of legitimacy.
-- There is a reason for everything that happens.
-- Find your own purpose in life.
-- Do not be a slave to time.
-- Appreciate things for what they are -- not for what they can give you.
-- Do not allow yourself to be dominated by the thoughts or expectations of others.
-- Do not be concerned with what others think of you, either.
-- Remember, you are not your body.
-- Fear not -- even pain and certainly not death.
-- Be open to life, and live it to its fullest.
-- Money and material things are not particularly important in the scheme of things.
-- Helping others is what counts in life.
-- Do not trouble yourself with competition -- just enjoy the show.
The only one that seems to fit in any manner is the "you are not yoru body" conclusion. However, in light of the studies showing that such experiences are not a result of some metaphyical realm, but instead simply of natural effects, this statement is directly contradicted.
However, if you're going to ignore such things and are really interested in drawing conclusions from this, here's a few that I'd recommend:
-- Since religious affiliation doesn't play a role in getting to such a paradise, it proves that all religions are equally wrong.
-- There is a life after death so why bother doing anything worhtwhile in this one?
-- The article mentions that injuries in the afterlife are miraculously healed, so why not go chop someone's arm off?
If you haven't caught the sarcasm, let me take this opporunity to point out that each of those was sarcastic and, when viewed in light of the complete body of evidence, cannot stand. However, I doubt any amount of evidence would convice those that what they saw wasn't real. I've not had such an experience, so I suppose I have no room to pass judgement. Nor do I have room to pass judgement on people that have been abducted by aliens, or seen bigfoot, etc...
Obama: Courting Disaster
Yahoo news, recently posted an article on comments made by Illinois' Democratic senator Barack Obama regarding his views on separation of church and state. Surprisingly for a democrat, he feels that this wall is too high and the article highlights many rather unappetizing comments he made.
The article points out that Obama has chastized fellow democrats for failing to "acknowledge the power of faith in the lives of the American people". I feel that this is an incorrect statement. I have no doubt that democrats are well aware of how effectively the faith card can be played to garner votes. I feel that many democrats just feel that there are more important things to our country than a belief in a higher power and that they should not have to bow to such ridiculous interests.
His next comment is one I personally agree with:
When someone is expressing their own convictions, there is no problem with it. But when they are acting as a representative for our country, expressing such convictions are out of place. They do not represent only those that share their faith, but must also represent the rapidly growing portion of the population that expresses no religious affiliation.
He claims that "[s]ecularists are wrong when they ask believers to leave their religion at the door before entering the public square." Yet no justification is given as to why our tax dollars should go to politicians who use their office to pronounce, promote, and prosetlyze their faith. Especially given that our constitution forbids such actions.
Obama goes on to claim:
Some would say that Obama is a demonstration that faith and the democratic party are not inseperable. I, however, would conclude that he merely demonstrats that when your opponent in the election is caught in a scandal just before the election, anyone can get elected.
The article points out that Obama has chastized fellow democrats for failing to "acknowledge the power of faith in the lives of the American people". I feel that this is an incorrect statement. I have no doubt that democrats are well aware of how effectively the faith card can be played to garner votes. I feel that many democrats just feel that there are more important things to our country than a belief in a higher power and that they should not have to bow to such ridiculous interests.
His next comment is one I personally agree with:
Not every mention of God in public is a breach to the wall of separation. Context mattersAs I mentioned, I agree strongly with this statement. The first ammendment guarantees religious freedoms which include the expression of such religions. However, there are times when expressing such things is appropriate, and times when it is not.
When someone is expressing their own convictions, there is no problem with it. But when they are acting as a representative for our country, expressing such convictions are out of place. They do not represent only those that share their faith, but must also represent the rapidly growing portion of the population that expresses no religious affiliation.
He claims that "[s]ecularists are wrong when they ask believers to leave their religion at the door before entering the public square." Yet no justification is given as to why our tax dollars should go to politicians who use their office to pronounce, promote, and prosetlyze their faith. Especially given that our constitution forbids such actions.
Obama goes on to claim:
It is doubtful that children reciting the Pledge of Allegiance feel oppressed or brainwashed as a consequence of muttering the phrase 'under God'I really wonder if Obama has bothered garnering an opinion from secularists before venturing to make such a statement. I will gladly speak for myself and say that I did feel oppressed when forced to pledge to a nation under a God I did not believe in. As such, I refused to recite the words, and was ostracized as a result. Many other members of SOMA and other atheistic groups have shared similar stories.
Some would say that Obama is a demonstration that faith and the democratic party are not inseperable. I, however, would conclude that he merely demonstrats that when your opponent in the election is caught in a scandal just before the election, anyone can get elected.
Wednesday, June 28, 2006
Astronomy Internship - Day 19
Today I started off with a bit more tinkering of parameters on the second image. I was able to get the subtracted image looking a little better, but not much. We've determined one of the biggest causes of error is that the focus wasn't consistent across the CCD. In reality, this is pretty typical given that every telescope design has some sort of inherent abberation. It's also entirely possible that the CCD wasn't perfectly aligned with the focal plane.
Either way, the best subtraction seems to be in the center. Towards the top it's a bit off, and for the bottom it's quite poor. Once I finished the second image, Dr. Sandquist advised me to go ahead and process the rest of them since I seem to have found the settings that work best.
At 11:00, Dr. Sandquist gave us a brief presentations on giving presentations since we have to do that Friday. Although he recommended a few things I didn't have, I think I'm going to ignore them. For instance, I don't really feel it's necessary to have a summary slide for a 5 minute presentation. I don't think anyone's memory is that bad.
I also spent a bit of time today trying to identify the single variable star Crinklaw & Talbert identified amidst the few thousand stars in the images. To do so, I took the finding chart from their paper, printed it out, and tried to match it up with our images. If you'd like to play along, here's the images:
This is the finder chart. The variable star is identified by the red circle. It may help to click to view the image in full and print it.
Here's the actual image I'm working with (with a little photoshopping of the levels to increase contrast).
NOTE: Just as I had to deal with, the two images may not be the same scale, area, center, or orientation! It took me about 3 minutes to locate. How quickly can you do it?
If you need the answer, click here.
At this point, I took a break for lunch and decided to take a quick nap. Quick of course meaning a little over 2 hours. When I woke up it was almost time for dinner so I decided to spend the little bit of time before then making a few quick changes to my powerpoint as I've decided that there my be a bit too much information for a 5 minute presentation, and I should drop a slide or two.
I did, however, add a few slides at the beginning as a refresher on properties of open clusters since not everyone in the group has much astronomy background. Once I made these changes, I Emailed it to my advisor back in Kansas for approval.
Either way, the best subtraction seems to be in the center. Towards the top it's a bit off, and for the bottom it's quite poor. Once I finished the second image, Dr. Sandquist advised me to go ahead and process the rest of them since I seem to have found the settings that work best.
At 11:00, Dr. Sandquist gave us a brief presentations on giving presentations since we have to do that Friday. Although he recommended a few things I didn't have, I think I'm going to ignore them. For instance, I don't really feel it's necessary to have a summary slide for a 5 minute presentation. I don't think anyone's memory is that bad.
I also spent a bit of time today trying to identify the single variable star Crinklaw & Talbert identified amidst the few thousand stars in the images. To do so, I took the finding chart from their paper, printed it out, and tried to match it up with our images. If you'd like to play along, here's the images:
This is the finder chart. The variable star is identified by the red circle. It may help to click to view the image in full and print it.
Here's the actual image I'm working with (with a little photoshopping of the levels to increase contrast).
NOTE: Just as I had to deal with, the two images may not be the same scale, area, center, or orientation! It took me about 3 minutes to locate. How quickly can you do it?
If you need the answer, click here.
At this point, I took a break for lunch and decided to take a quick nap. Quick of course meaning a little over 2 hours. When I woke up it was almost time for dinner so I decided to spend the little bit of time before then making a few quick changes to my powerpoint as I've decided that there my be a bit too much information for a 5 minute presentation, and I should drop a slide or two.
I did, however, add a few slides at the beginning as a refresher on properties of open clusters since not everyone in the group has much astronomy background. Once I made these changes, I Emailed it to my advisor back in Kansas for approval.
A GIGAPIXEL camera?!
As I've pointed out before, every photon in astronomy is precious. Thus astronomers have switched to CCD detectors over the last few decades. A paper I was recently reading, published in 1991, discussed a camera with a modest 800 x 800 pixels. Barely more than many webcams by today's standards, but fairly large for the time.
Today, a decent digital camera will run around 4 megapixels. Astronomical CCDs are often much larger, and are frequently glued side by side to make even larger arrays reaching into the hundreds of megapixels.
However, even these digital monstrosities will soon be overpowered. According to New Scientist, the Pan-STARRS telescopes, which are due to go into operation soon to hunt for potentially dangerous asteroids, will be to a 1.4 gigapixel camera in March 2007! For those that aren't up on your metric, that means 1000 megapixels!
Today, a decent digital camera will run around 4 megapixels. Astronomical CCDs are often much larger, and are frequently glued side by side to make even larger arrays reaching into the hundreds of megapixels.
However, even these digital monstrosities will soon be overpowered. According to New Scientist, the Pan-STARRS telescopes, which are due to go into operation soon to hunt for potentially dangerous asteroids, will be to a 1.4 gigapixel camera in March 2007! For those that aren't up on your metric, that means 1000 megapixels!
Tuesday, June 27, 2006
Astronomy Internship - Day 18
A bit more tinkering today on trying to reduce the leftover light. Sadly, nothing at this stage seems to help.
Thus, Dr. Sandquist advised me to back up a few steps and to one of the most annoying steps all over, but even more tediously. This step involves looking at the radial plot of intensity vs. radius from the center of a star, making sure it has a smooth distribution (should look like half a bell curve), and then finding that star on the actual image (one star out of >2000) to make sure it doesn't have any close companions or anything else that might screw things up.
This meant manually going through 187 stars, each of which took about a minute to do. Two hours later, I had a new set of model stars to try out. Plugging it into the script I generated a new image and magically, all leftover light was reduced to half of what it was before or better!
Feeling that there was little more that could be done to improve things, Dr. Sandquist advised me to move on to the next image and see how well things look for that.
Since I knew what I was doing this time and didn't have to go the 171 steps down the hall to Dr. Sandquist's office every half hour, I was able to do things much quicker this time. Again, I had to go through the tedious task of visually inspecting each star that the computer deemed a good candidate to model the shape of. This time there were "only" 151 of them and I ended up keeping 130.
At that point it was 5:30 and I headed off to dinner. Afterwards I finished up my Powerpoint presentation for the talk I'll be giving on Friday. For the most part, it covers everything I said a few days ago, but just includes specific numbers, bigger words, and more citations. I'll be sending that to my advisor in the next day or two for her approval and then I'll post it here.
Thus, Dr. Sandquist advised me to back up a few steps and to one of the most annoying steps all over, but even more tediously. This step involves looking at the radial plot of intensity vs. radius from the center of a star, making sure it has a smooth distribution (should look like half a bell curve), and then finding that star on the actual image (one star out of >2000) to make sure it doesn't have any close companions or anything else that might screw things up.
This meant manually going through 187 stars, each of which took about a minute to do. Two hours later, I had a new set of model stars to try out. Plugging it into the script I generated a new image and magically, all leftover light was reduced to half of what it was before or better!
Feeling that there was little more that could be done to improve things, Dr. Sandquist advised me to move on to the next image and see how well things look for that.
Since I knew what I was doing this time and didn't have to go the 171 steps down the hall to Dr. Sandquist's office every half hour, I was able to do things much quicker this time. Again, I had to go through the tedious task of visually inspecting each star that the computer deemed a good candidate to model the shape of. This time there were "only" 151 of them and I ended up keeping 130.
At that point it was 5:30 and I headed off to dinner. Afterwards I finished up my Powerpoint presentation for the talk I'll be giving on Friday. For the most part, it covers everything I said a few days ago, but just includes specific numbers, bigger words, and more citations. I'll be sending that to my advisor in the next day or two for her approval and then I'll post it here.
Astronomy Internship - Day 17
Back to real work today. I finally finished the photometry for the first of 9 frames. However, in the analysis, it seems that the routine missed ~2-5% of the light from each star it was trying to subtract out. Apparently this is a huge uncertainty. Thus, the next 6 hours were spent adjusting settings, trying to get to less than 1%.
Fortunately, Dr. Sandquist has provieded me with another computer script that did what I was doing manually, in an hour, in about 3 minutes. However, dispite the program outputting the subtracted images more rapidly, the large majority of that 6 hours was comparing the outputted images to the original to see exactly how much light was leftover. Either that or cursing that IRAF for losing my cursor.
Sadly, no matter how much I played with the settings, we didn't seem to be able to get it below 2%. At about 6:00 I finally gave up for the day and headed off to dinner. Surprisingly, everything was edible. Horay for old people! Boo for the swarms of children monopolizing the game room and TVs.
Fortunately, Dr. Sandquist has provieded me with another computer script that did what I was doing manually, in an hour, in about 3 minutes. However, dispite the program outputting the subtracted images more rapidly, the large majority of that 6 hours was comparing the outputted images to the original to see exactly how much light was leftover. Either that or cursing that IRAF for losing my cursor.
Sadly, no matter how much I played with the settings, we didn't seem to be able to get it below 2%. At about 6:00 I finally gave up for the day and headed off to dinner. Surprisingly, everything was edible. Horay for old people! Boo for the swarms of children monopolizing the game room and TVs.
Astronomy Internship - Day 16
Today was another day of doing absolutely nothing. We've had a large group of the senior citizens move in, so hopefully, that will mean an improvement in food quality. There's also a new group of sports camps.
Sunday, June 25, 2006
More writing on the wall - Homegrown Terrorists
The media has been buzzing recently about a group of 7 men arrested in Miami for plotting to destroy the Sears tower. For some reason, many of the articles seem to focus on the men being American with some sort of shock and awe.
"How ever could an American not do anything but love their country?" they seem to profess.
Is our collective memory so short that we can't remember back to 1995 when another "homegrown" terrorist bombed the Alfred P. Murrah Building in Oklahoma City?
Do we blithely forget that our good and loving "Pro-Life" activists have blown up abortion clinics?
America may not be the fertile soil for terroists that the mideast is, but to be so ignorant of the fact that our nation has and will produce malcontent extremists is to invite disaster.
"How ever could an American not do anything but love their country?" they seem to profess.
Is our collective memory so short that we can't remember back to 1995 when another "homegrown" terrorist bombed the Alfred P. Murrah Building in Oklahoma City?
Do we blithely forget that our good and loving "Pro-Life" activists have blown up abortion clinics?
America may not be the fertile soil for terroists that the mideast is, but to be so ignorant of the fact that our nation has and will produce malcontent extremists is to invite disaster.
Saturday, June 24, 2006
Astronomy Internship - Day 15
Today was spent doing absolutely no astronomy.
I slept fairly late again today. Once I got breakfast I went out to find some stamps. I figured the bookstore might sell them. But, although the bookstore is generally open on Saturdays, it was closed today. So I ended up walking several miles in order to find some.
Afterwards, I spent a good amount of time working on filling out my application for financial aid. The rest of the day has been primarily playing video games.
I slept fairly late again today. Once I got breakfast I went out to find some stamps. I figured the bookstore might sell them. But, although the bookstore is generally open on Saturdays, it was closed today. So I ended up walking several miles in order to find some.
Afterwards, I spent a good amount of time working on filling out my application for financial aid. The rest of the day has been primarily playing video games.
Friday, June 23, 2006
Astronomy Internship - Day 14
Today I spent most of my day working on playing with the parameters for DAOPHOT's star finding algorithm to see if I couldn't get it to pick up some of the fainter ones.
It seems that biggest problem for detecting them is that their "shape" is slightly different. One of the input parameters is telling the program how far from the center of the star it is till its light has been reduced by 50% (this is called the Full Width, Half Max or FWHM). Ideally stars are infintely small, point sources. The reason they get spread out is due (primarily) to the atmospheric turbulance. But since we're looking at a small section of sky, they should all be spread out in the same way, which is why every star should have the same FWHM. Why some of these fainter ones don't is a bit strange. But they're not so far off that we think something went wrong. Just far enough that the program isn't feeling the love.
Once we got something that we were satisfied with, the next task was to do a rough first estimate on the brightness of each star. Since we're looking at a crowded cluster, this is very rough because stars are so close together that sometimes their light overalaps and thus, you're looking at two stars at the same time. This will be sorted out later in a process I might try to go into detail on at a later date (it's rather complex).
The program does that for us for the most part, so it didn't take much time.
Our next step was to find some stars that were good candidates for modeling the "shape" of so that we could attempt to estimate the shape for all other stars and then effectively subtract them out so we can look at one star at a time (note: when I say "shape" I don't mean 3D shape, but rather how the light is spread out and how bright it is on the CCD).
Unfortunately, the finding program detected 2989 things it thought were stars. Sorting through each of them manually does not sound fun. Thus, another set of programs are used that automatically cuts the options down to a few dozen based on how bright they are, how idealized their "shape" is, how nearby other stars are, etc...
But as luck would have it, the first of the three selection programs crashed repeatedly. Dr. Sandquist went to go check it out but wasn't able to immediately figure out why.
After about an hour, he fixed it and I only had to go through ~150 stars. I decided that I'd gotten enough accomplished for the day so I headed back to the dorm. That evening a few of us watched V for Vendetta in the lounge downstairs.
It seems that biggest problem for detecting them is that their "shape" is slightly different. One of the input parameters is telling the program how far from the center of the star it is till its light has been reduced by 50% (this is called the Full Width, Half Max or FWHM). Ideally stars are infintely small, point sources. The reason they get spread out is due (primarily) to the atmospheric turbulance. But since we're looking at a small section of sky, they should all be spread out in the same way, which is why every star should have the same FWHM. Why some of these fainter ones don't is a bit strange. But they're not so far off that we think something went wrong. Just far enough that the program isn't feeling the love.
Once we got something that we were satisfied with, the next task was to do a rough first estimate on the brightness of each star. Since we're looking at a crowded cluster, this is very rough because stars are so close together that sometimes their light overalaps and thus, you're looking at two stars at the same time. This will be sorted out later in a process I might try to go into detail on at a later date (it's rather complex).
The program does that for us for the most part, so it didn't take much time.
Our next step was to find some stars that were good candidates for modeling the "shape" of so that we could attempt to estimate the shape for all other stars and then effectively subtract them out so we can look at one star at a time (note: when I say "shape" I don't mean 3D shape, but rather how the light is spread out and how bright it is on the CCD).
Unfortunately, the finding program detected 2989 things it thought were stars. Sorting through each of them manually does not sound fun. Thus, another set of programs are used that automatically cuts the options down to a few dozen based on how bright they are, how idealized their "shape" is, how nearby other stars are, etc...
But as luck would have it, the first of the three selection programs crashed repeatedly. Dr. Sandquist went to go check it out but wasn't able to immediately figure out why.
After about an hour, he fixed it and I only had to go through ~150 stars. I decided that I'd gotten enough accomplished for the day so I headed back to the dorm. That evening a few of us watched V for Vendetta in the lounge downstairs.
Thursday, June 22, 2006
Astronomy Internship - Day 13
My day started today far earlier than I'd have liked it to. My roomate has gotten into a very annoying habit of setting his alarm extremely early and then hitting the snooze alarm repeatedly, for sometimes as much as an hour.
Unfortunately for me, I'm a light sleeper and once I'm awake, it generally takes me a half hour to get back to sleep. With an alarm going off every 10 minutes, this means that I don't get back to sleep.
Finally, he gets up at around 7:00. By 7:30 I'm just about to fall back asleep when the janitorial staff decides it would be a good idea to start vacuuming the hall outside my door. So I'm kept up for another half hour.
I finally decided to just sleep in and catch up on the sleep I'd lost.
I eventually got up around 10:00 and headed over to the astronomy building to play with DAOPHOT. The process did not go terribly smoothly.
The first problem I had is that, upon starting, it asks to confirm that a number of parameters are set correctly. Given that they were default values, I was quite sure that they were not. However, the logsheet for when the images were taken did not contain the information I needed. Thus, I had to find Dr. Sandquist and obtain the information from him.
My next problem was getting the images to open. It turns out that, since I had to go to Dr. Sandquist's directory on the server and was running the program from there, it wouldn't let me open images in my directory since I didn't have permission to do things in his directory.
Once we go the image open, the next thing to do was have the computer find all the stars in the image. Since it's a cluster I'm analyzing, there can be several hundred to a few thousand stars, which is why we make the computer do it.
Unfortunately, fine tuning the algorithm to do this is quite tricky. The first time through it was able to find the bright stars without any problem, but completely missed the dim ones, yet claimed to find several where there were none.
After a bit of tinkering, I was able to improve it slightly, and it picked up most real stars, with the exception of the faintest, but seemed to still be finding stars in completely blank fields.
I tinkered a bit longer and gave up for the day around 3:30 because staring at the computer was making my head hurt. I went back to my room and did some reading, and took a short nap before dinner.
After dinner I came back and laid down again because I had a migraine. Around 8:30, I went out for a walk which finally made my head feel better.
When I got back at 10:00 I began working on the Powerpoint presentation for our talks next week over our project. I'll be sure to post the Powerpoint file after the talk which should be next Friday.
Unfortunately for me, I'm a light sleeper and once I'm awake, it generally takes me a half hour to get back to sleep. With an alarm going off every 10 minutes, this means that I don't get back to sleep.
Finally, he gets up at around 7:00. By 7:30 I'm just about to fall back asleep when the janitorial staff decides it would be a good idea to start vacuuming the hall outside my door. So I'm kept up for another half hour.
I finally decided to just sleep in and catch up on the sleep I'd lost.
I eventually got up around 10:00 and headed over to the astronomy building to play with DAOPHOT. The process did not go terribly smoothly.
The first problem I had is that, upon starting, it asks to confirm that a number of parameters are set correctly. Given that they were default values, I was quite sure that they were not. However, the logsheet for when the images were taken did not contain the information I needed. Thus, I had to find Dr. Sandquist and obtain the information from him.
My next problem was getting the images to open. It turns out that, since I had to go to Dr. Sandquist's directory on the server and was running the program from there, it wouldn't let me open images in my directory since I didn't have permission to do things in his directory.
Once we go the image open, the next thing to do was have the computer find all the stars in the image. Since it's a cluster I'm analyzing, there can be several hundred to a few thousand stars, which is why we make the computer do it.
Unfortunately, fine tuning the algorithm to do this is quite tricky. The first time through it was able to find the bright stars without any problem, but completely missed the dim ones, yet claimed to find several where there were none.
After a bit of tinkering, I was able to improve it slightly, and it picked up most real stars, with the exception of the faintest, but seemed to still be finding stars in completely blank fields.
I tinkered a bit longer and gave up for the day around 3:30 because staring at the computer was making my head hurt. I went back to my room and did some reading, and took a short nap before dinner.
After dinner I came back and laid down again because I had a migraine. Around 8:30, I went out for a walk which finally made my head feel better.
When I got back at 10:00 I began working on the Powerpoint presentation for our talks next week over our project. I'll be sure to post the Powerpoint file after the talk which should be next Friday.
Astronomy Internship - Day 12
Today was our first day without any real supervision. When I woke up this morning, my advisor still hadn't replied to my Email asking whether I should continue using IRAF to reduce data, or if I should do as Dr. Sandquist recommended and use a stand alone program known as DAOPHOT. So I spent my morning continuing to read journal articles on the cluster in question.
After lunch, my advisor had finally relplied and told me to go with DAOPHOT. So I headed over to the astronomy building to find Dr. Sandquist. He photocopied the ~80 page manual for DAOPHOT and pointed out several sections I should become familiar with.
Once I got a binder to keep this rather large stack of papers in, I headed back to my room and read until dinner.
We learned at dinner that our tower is also being used by a cheerleading camp. Oh joy. The dining hall was filled with scores of chatty teens. Ew.
After dinner, four of us played some foosball and pool in the tower's game room. I managed to remain undefeated in foosball (3 team games and 1 solo 1v1), and won at pool (although only because my opponent put the 8-ball in the wrong pocket).
Once that was finished, I headed back to my room and did some more reading. About 9:00, I finally grew tired of that and played around on the internet for the rest of the night.
Tomorrow I'll hopefully be knowledgeable enough about this program to start processing data.
After lunch, my advisor had finally relplied and told me to go with DAOPHOT. So I headed over to the astronomy building to find Dr. Sandquist. He photocopied the ~80 page manual for DAOPHOT and pointed out several sections I should become familiar with.
Once I got a binder to keep this rather large stack of papers in, I headed back to my room and read until dinner.
We learned at dinner that our tower is also being used by a cheerleading camp. Oh joy. The dining hall was filled with scores of chatty teens. Ew.
After dinner, four of us played some foosball and pool in the tower's game room. I managed to remain undefeated in foosball (3 team games and 1 solo 1v1), and won at pool (although only because my opponent put the 8-ball in the wrong pocket).
Once that was finished, I headed back to my room and did some more reading. About 9:00, I finally grew tired of that and played around on the internet for the rest of the night.
Tomorrow I'll hopefully be knowledgeable enough about this program to start processing data.
Wednesday, June 21, 2006
Astronomy Internship - Day 11
Today was our last day of crash courses into everything imaginable. Today's topic: Programming in Fortran. Yeah, not the most exciting thing, but not terribly difficult since I've had a course in C++ programming already. Although each one is a different language and has slightly different syntax, once you learn one, the logic behind them is all pretty much the same. So the practical application we had wasn't difficult.
We also had our last premium lunch today in which we were given $7.75 on a little card to spend at any of the campus resturaunts. Tomorrow all our meals will be being served from the campus dining halls. The quality and selection has improved recently because several camps of hyperactive teenagers and choirs seem to have been visiting the campus recently. Thus, with the massive influx of people (in relation to the 20-30 that were at the dining halls before the other groups showed up), the dining halls have been forced to have more options.
Additionally, the building in which I'm living (University Towers), apparently gets rented out to the general public during the summer as well, and to keep from looking bad, the staff here says food quality improves for their stay, which should be the rest of the program.
I've also been piecing together my goals for this project with NGC 7142 a bit better. It seems our main goal is to basically replicate the
Crinklaw & Talbert paper from 1991, but with better data and in a broader selection fo filters.
The question now is, which program to use to do the photometry? While we've been learning to use IRAF for the past week and a half, it's still not the easiest of programs out there. Dr. Sandquist has recommended using another that's more suitable for what I'm trying to do. However, the problem is that, should I be continuing this work when I return to Kansas, KU may not have these other programs, whereas IRAF is more universal since it's by far the most widely used (and free). I Emailed my advisor earlier today to get her input, but haven't heard back from her yet.
So hopefully, by tomorrow I'll have heard back and I can get started on some real work.
We also had our last premium lunch today in which we were given $7.75 on a little card to spend at any of the campus resturaunts. Tomorrow all our meals will be being served from the campus dining halls. The quality and selection has improved recently because several camps of hyperactive teenagers and choirs seem to have been visiting the campus recently. Thus, with the massive influx of people (in relation to the 20-30 that were at the dining halls before the other groups showed up), the dining halls have been forced to have more options.
Additionally, the building in which I'm living (University Towers), apparently gets rented out to the general public during the summer as well, and to keep from looking bad, the staff here says food quality improves for their stay, which should be the rest of the program.
I've also been piecing together my goals for this project with NGC 7142 a bit better. It seems our main goal is to basically replicate the
Crinklaw & Talbert paper from 1991, but with better data and in a broader selection fo filters.
The question now is, which program to use to do the photometry? While we've been learning to use IRAF for the past week and a half, it's still not the easiest of programs out there. Dr. Sandquist has recommended using another that's more suitable for what I'm trying to do. However, the problem is that, should I be continuing this work when I return to Kansas, KU may not have these other programs, whereas IRAF is more universal since it's by far the most widely used (and free). I Emailed my advisor earlier today to get her input, but haven't heard back from her yet.
So hopefully, by tomorrow I'll have heard back and I can get started on some real work.
Tuesday, June 20, 2006
Astronomy Internship - Day 10
Today's session was on a process known as Spectometry which analyzes, obviously, the spectrum of the star. After the session, I spent most of the evening reading over papers.
Nothing terribly exciting.
Nothing terribly exciting.
Monday, June 19, 2006
Astronomy Internship - Day 9
I ended up printing off another ~60 pages of journal articles yesterday afternoon but haven't had too much time to peruse them. I'm still waiting for word from my advisor on some clarifications on what our research goals are.
But of course, the highlight of the day was the trip up to Laguna Observatory. So here's the grand tour:
The trip started off with the long drive up into the mountains. When leaving the main highway, we had already gone from an elevation of a few hundred feet, to 4,000.
By the time we reached the visitor parking, we'd passed 5,000. Along the way were several signs warning that cows may be on the road. Dr. Sandquist warned us to be careful about this since, in California, there's apparently laws that make the drivers liable for cows on the road.
Once we reached the visitor parking, we had to walk up another trail that probably climed another few hundred feet:
Meanwhile, the professors drove:
But eventually we made it to the top:
Inside one of the buildings at the main facility was a small museum with some interesting items.
This one is an antique telescope that was built around 1800.
This piece is known as a "blink comparator". Back when astronomy was done on glass photographic plates, astronomers would put two plates of the same field of sky in the left and right piece, align them, and then the device would project an image of them onto a screen at the bottom, flipping between the two images. This would allow astronomers to pick out objects that changed between frames. A device similar to this one was used by Clyde Tombaugh to discover Pluto in just this manner. It also works well for stars that vary in brightness.
This device is a microdesensitometer. A photographic plate would be placed on the glass table and a light on the top arm would shine through it to a device which would measure the intensity underneath. By moving it around the plate it was possible to generate graphs of the brightness levels such as this one:
After exploring the museum (which contained many more items that wouldn't be of too much interest if you're not into all sorts of techincal stuff), we headed out to see the telescopes.
The first stop was the largest on the mountain which housed a 40" telescope (telescopes are measured in the diameter of their primary mirror).
First thing inside was the aluminizing chamber. Since telescope mirrors are made of glass, they have to be coated with a thin layer of aluminum. Eventually they get dirty, and the coating has to be redone. This is the device that's used to do so.
Here's one of the tanks of liquid nitrogen that are used to keep the CCD camera cool which I'll explain more about in a later post.
And finally, here's the 40" telescope. It's currently in the process of being refurbished, so the imaging devices aren't attached at the time. Our tour guide pointed out that this telescope weighs somewhere around 47,000 pounds!
This is the control room for the telescope. It's in the next room over. While there was originally a window from this room to the room housing the telescope, it has since been boarded over to prevent any light from the computers from interfering with the imaging. Thus, the telescope (as are all major observatories), is completely controlled by the computers.
While this may not look like much, this device is known as a flat field. It probably doesn't mean anything to you know, but will once I finish up my next Astronomical Data post.
Again, this image may not look like anything special, but what you'll notice is that next to the standard lightbulb is another one. This one is red and only red lights are used while observing. This is because red light allows astronomers to still see but not lose their night vision.
This dome will eventually house a telescope that is being built jointly with my school (University of Kansas), known as the ULTRA. Essentially it's an ambitious project to see if it's possible to construct a telescope mirror to research grade specifications using graphite as opposed to glass. The primary mirror will be 16" in diameter but be light enough to be carried by a single person, whereas glass mirrors of the same diameter will weigh several thousand pounds. The telescope was originally planned to go into operation in fall of 2005, but as with anything, it's overschedule and is now expected fall of 2006. Another interesting note is that this telescope will be completely automated, which means that we'll be able to controll it from Kansas!
These buildings are the dormatories for observers. You'll notice they have no windows.
This telescope houses the 21" telescope.
This is the 21" scope.
This nifty device is a microwave transmitter which allows for direct communication with the campus. Images can be taken with the telescopes on the mountain and immediately downloaded to campus. The small security camera is the live webcam which I posted the image for yesterday.
That concluded our tour so I (looking not so angry) and the rest of the group headed back down to the main buildings for dinner:
Once dinner was over it was time to do a little bit of observing.
This is the guest observatory which houses another 21" telescope.
That would be the scope.
Sadly, I couldn't get any images through the eyepiece of camera, but I will point out that they were fantastic.
From the top of the mountain we could see Tiajuana off in the distance.
At around 11:00, we concluded our observing and headed back to campus.
But of course, the highlight of the day was the trip up to Laguna Observatory. So here's the grand tour:
The trip started off with the long drive up into the mountains. When leaving the main highway, we had already gone from an elevation of a few hundred feet, to 4,000.
By the time we reached the visitor parking, we'd passed 5,000. Along the way were several signs warning that cows may be on the road. Dr. Sandquist warned us to be careful about this since, in California, there's apparently laws that make the drivers liable for cows on the road.
Once we reached the visitor parking, we had to walk up another trail that probably climed another few hundred feet:
Meanwhile, the professors drove:
But eventually we made it to the top:
Inside one of the buildings at the main facility was a small museum with some interesting items.
This one is an antique telescope that was built around 1800.
This piece is known as a "blink comparator". Back when astronomy was done on glass photographic plates, astronomers would put two plates of the same field of sky in the left and right piece, align them, and then the device would project an image of them onto a screen at the bottom, flipping between the two images. This would allow astronomers to pick out objects that changed between frames. A device similar to this one was used by Clyde Tombaugh to discover Pluto in just this manner. It also works well for stars that vary in brightness.
This device is a microdesensitometer. A photographic plate would be placed on the glass table and a light on the top arm would shine through it to a device which would measure the intensity underneath. By moving it around the plate it was possible to generate graphs of the brightness levels such as this one:
After exploring the museum (which contained many more items that wouldn't be of too much interest if you're not into all sorts of techincal stuff), we headed out to see the telescopes.
The first stop was the largest on the mountain which housed a 40" telescope (telescopes are measured in the diameter of their primary mirror).
First thing inside was the aluminizing chamber. Since telescope mirrors are made of glass, they have to be coated with a thin layer of aluminum. Eventually they get dirty, and the coating has to be redone. This is the device that's used to do so.
Here's one of the tanks of liquid nitrogen that are used to keep the CCD camera cool which I'll explain more about in a later post.
And finally, here's the 40" telescope. It's currently in the process of being refurbished, so the imaging devices aren't attached at the time. Our tour guide pointed out that this telescope weighs somewhere around 47,000 pounds!
This is the control room for the telescope. It's in the next room over. While there was originally a window from this room to the room housing the telescope, it has since been boarded over to prevent any light from the computers from interfering with the imaging. Thus, the telescope (as are all major observatories), is completely controlled by the computers.
While this may not look like much, this device is known as a flat field. It probably doesn't mean anything to you know, but will once I finish up my next Astronomical Data post.
Again, this image may not look like anything special, but what you'll notice is that next to the standard lightbulb is another one. This one is red and only red lights are used while observing. This is because red light allows astronomers to still see but not lose their night vision.
This dome will eventually house a telescope that is being built jointly with my school (University of Kansas), known as the ULTRA. Essentially it's an ambitious project to see if it's possible to construct a telescope mirror to research grade specifications using graphite as opposed to glass. The primary mirror will be 16" in diameter but be light enough to be carried by a single person, whereas glass mirrors of the same diameter will weigh several thousand pounds. The telescope was originally planned to go into operation in fall of 2005, but as with anything, it's overschedule and is now expected fall of 2006. Another interesting note is that this telescope will be completely automated, which means that we'll be able to controll it from Kansas!
These buildings are the dormatories for observers. You'll notice they have no windows.
This telescope houses the 21" telescope.
This is the 21" scope.
This nifty device is a microwave transmitter which allows for direct communication with the campus. Images can be taken with the telescopes on the mountain and immediately downloaded to campus. The small security camera is the live webcam which I posted the image for yesterday.
That concluded our tour so I (looking not so angry) and the rest of the group headed back down to the main buildings for dinner:
Once dinner was over it was time to do a little bit of observing.
This is the guest observatory which houses another 21" telescope.
That would be the scope.
Sadly, I couldn't get any images through the eyepiece of camera, but I will point out that they were fantastic.
From the top of the mountain we could see Tiajuana off in the distance.
At around 11:00, we concluded our observing and headed back to campus.
Saturday, June 17, 2006
Astronomy Internship - Day 8
As predicted, I spent a good deal of my time reading through the previous literature on NGC 7142. The most recent publication I was able to find was from 1991. The earliest I had printed was 1962.
So here's a brief intro to NGC 7142:
NGC 1742 is an open cluster located in Cepheus. Open clusters are assosciations of gravitationally bound stars that will have anywhere from a few thousand to tens of thousands of stars (for reference, globular clusters generally have on the order of hundreds of thousands).
In the picture above, NGC 7142 is the little knot just below and to the right of center. However, you'll probably notice the nebula just up and to the left of it. This is NGC 7129. It's a reflection nebula. This type of nebula is lit by light reflecting off clouds of gas and dust.
However, its presence in the same region of the sky gives an indication that there will be difficulties in making scientifically meaningful measurements of the cluster because it's quite likely that the cloud of dust extends in front of NGC 7142. As I discussed in one of my earlier sections, clouds such as this will dim light that passes through them. However, it does not dim all wavelengths evenly. Red light passes through more easily.
In astronomy, we frequently compare how bright a star is at two different wavelengths (I'll explain this in more detail in an upcoming post). However, since this cloud is effecting the wavelenghts differently, it becomes difficult to make a meaningful assesment of the difference.
To get any sort of meaningful science, it will be necessary to somehow take this cloud into account. The problem then becomes determining how much of an effect this cloud has (known as the reddening). Unfortunately, there's no good way to do this.
And to make matters even more difficult, its strongly believed that the thickness across the face of the cluster isn't even! This introduces relatively large uncertanties into the determinations of all properties.
The most recently determined distance to the cluster is 1900 parsecs (6200 light years or 3.7 x 1016 miles) (Crinklaw & Talbert, 1991).
Another feature many expected to see was a relatively high number of variable stars of a rare type known as "W UMa". Another open cluster, NGC 188, shows many similarities to NGC 7142 and contains many of this type. Thus, it was suspected that NGC 7142 might as well. However, of the 1093 stars observed by Crinklaw & Talbert, only one was found to be a variable. Unfortunately, not enough observations were made to obtain a detailed enough light curve to determine of what type. However, indications from the partial light curves generated suggest it is most likely an eclipsing binary. Looking at the number of images obtained that I'll be working with, it's doubtful that I'll be able to make any further determination of the type of variable.
As far as age, the best determination has been that the cluster is between 3.5 x 109 and 4.5 x 109 years old with data favouring the older estimate. This makes it one of the oldest known clusters.
Tomorrow I'll be going to the lab and trying to find a few more papers that these ones referenced (some as early as 1945). In the evening, our group is going to Mount Laguna Observatory (MLO). The observatory has a pretty live webcam:
Refreshing the page should update the image.
So here's a brief intro to NGC 7142:
NGC 1742 is an open cluster located in Cepheus. Open clusters are assosciations of gravitationally bound stars that will have anywhere from a few thousand to tens of thousands of stars (for reference, globular clusters generally have on the order of hundreds of thousands).
In the picture above, NGC 7142 is the little knot just below and to the right of center. However, you'll probably notice the nebula just up and to the left of it. This is NGC 7129. It's a reflection nebula. This type of nebula is lit by light reflecting off clouds of gas and dust.
However, its presence in the same region of the sky gives an indication that there will be difficulties in making scientifically meaningful measurements of the cluster because it's quite likely that the cloud of dust extends in front of NGC 7142. As I discussed in one of my earlier sections, clouds such as this will dim light that passes through them. However, it does not dim all wavelengths evenly. Red light passes through more easily.
In astronomy, we frequently compare how bright a star is at two different wavelengths (I'll explain this in more detail in an upcoming post). However, since this cloud is effecting the wavelenghts differently, it becomes difficult to make a meaningful assesment of the difference.
To get any sort of meaningful science, it will be necessary to somehow take this cloud into account. The problem then becomes determining how much of an effect this cloud has (known as the reddening). Unfortunately, there's no good way to do this.
And to make matters even more difficult, its strongly believed that the thickness across the face of the cluster isn't even! This introduces relatively large uncertanties into the determinations of all properties.
The most recently determined distance to the cluster is 1900 parsecs (6200 light years or 3.7 x 1016 miles) (Crinklaw & Talbert, 1991).
Another feature many expected to see was a relatively high number of variable stars of a rare type known as "W UMa". Another open cluster, NGC 188, shows many similarities to NGC 7142 and contains many of this type. Thus, it was suspected that NGC 7142 might as well. However, of the 1093 stars observed by Crinklaw & Talbert, only one was found to be a variable. Unfortunately, not enough observations were made to obtain a detailed enough light curve to determine of what type. However, indications from the partial light curves generated suggest it is most likely an eclipsing binary. Looking at the number of images obtained that I'll be working with, it's doubtful that I'll be able to make any further determination of the type of variable.
As far as age, the best determination has been that the cluster is between 3.5 x 109 and 4.5 x 109 years old with data favouring the older estimate. This makes it one of the oldest known clusters.
Tomorrow I'll be going to the lab and trying to find a few more papers that these ones referenced (some as early as 1945). In the evening, our group is going to Mount Laguna Observatory (MLO). The observatory has a pretty live webcam:
Refreshing the page should update the image.
Astronauts like a good party too
Take a good look at this image from the ISS:
Notice anything funny? If you don't catch it, perhaps you might try checking out the high res version.
Still don't see it? A sharp eyed editor at SpaceRef.com noted something a bit odd:
Party balloons? It seems that the balloons were leftover from a surprise party for astronaut Jeff William's wife during a private family session a few weeks ago.
Notice anything funny? If you don't catch it, perhaps you might try checking out the high res version.
Still don't see it? A sharp eyed editor at SpaceRef.com noted something a bit odd:
Party balloons? It seems that the balloons were leftover from a surprise party for astronaut Jeff William's wife during a private family session a few weeks ago.
Teaching the Psychiatry Controversy
If you've followed my blog for any time, you'll be well aware that I think the ID slogan of "teach the controversy" is nothing but a baseless appeal to uninformed citizen's sense of fairness. If there's a controversy, both sides deserve to be heard. However, with ID, there is no credible scientific controversy.
But ID isn't the only false religiously driven controversy out there today. The new pet religion of crazies like Tom Cruise, Scientology, seeks to undermine psychiatry. Their claim is that psychiatric drugs are extremely harmful. They point out things such as the fact that although we frequently use terms like "chemical imbalance", scientists have never been able to determine what chemicals these would be.
What they fail to note the overwhelming success of treatments. Instead, they cherry pick examples that support their position. But in reality, even before science developed the germ theory of disease and illness was believed to be the cause of humors or demons, we were still able to recognize that certain plants had excellent restorative powers.
Thus, it does't necessarily require a complete understanding of the cause to recognize a treatment.
But as with the ID movement, Scientologists damn the facts and support "teaching the controversy". Unfortunately for them, they don't have the full support of an entire political party to push their agenda. However, it seems they're trying.
According to the Chicago Tribune, Kenneth Dunkin (D) endorsed an exhibit that describes psychiatry as a pseudoscience and claims that it pushes pills and is, somehow, related to Nazism (sound familiar?).
The exhibit was created by "Citizens Commission on Human Rights", an organization created and paid for by the Church of Scientology (ie, their version of the Discovery Institute).
The display has promted visitors to contact the Illinois chapter of National Alliance for Mental Illness with complaints and confusion over the authority of the exhibit. Yet Dunkin stands by his sponsorship, saying, "There is a culture that says if you don't use this drug you can't be cured. In fact, no drug can cure you."
While I certainly agree that this culture is far too dependant on medications as a quick fix and a way to hide from underlying problems, so claim that medications can't assist in cures and are worthless is a dangerous extreme that is opposed almost universally by scientists.
These pseudoscientific "controversies" play on the ethical fairness many of us feel, but little on logic. Sadly this trend seems to be growing and threatens to undermine science.
But ID isn't the only false religiously driven controversy out there today. The new pet religion of crazies like Tom Cruise, Scientology, seeks to undermine psychiatry. Their claim is that psychiatric drugs are extremely harmful. They point out things such as the fact that although we frequently use terms like "chemical imbalance", scientists have never been able to determine what chemicals these would be.
What they fail to note the overwhelming success of treatments. Instead, they cherry pick examples that support their position. But in reality, even before science developed the germ theory of disease and illness was believed to be the cause of humors or demons, we were still able to recognize that certain plants had excellent restorative powers.
Thus, it does't necessarily require a complete understanding of the cause to recognize a treatment.
But as with the ID movement, Scientologists damn the facts and support "teaching the controversy". Unfortunately for them, they don't have the full support of an entire political party to push their agenda. However, it seems they're trying.
According to the Chicago Tribune, Kenneth Dunkin (D) endorsed an exhibit that describes psychiatry as a pseudoscience and claims that it pushes pills and is, somehow, related to Nazism (sound familiar?).
The exhibit was created by "Citizens Commission on Human Rights", an organization created and paid for by the Church of Scientology (ie, their version of the Discovery Institute).
The display has promted visitors to contact the Illinois chapter of National Alliance for Mental Illness with complaints and confusion over the authority of the exhibit. Yet Dunkin stands by his sponsorship, saying, "There is a culture that says if you don't use this drug you can't be cured. In fact, no drug can cure you."
While I certainly agree that this culture is far too dependant on medications as a quick fix and a way to hide from underlying problems, so claim that medications can't assist in cures and are worthless is a dangerous extreme that is opposed almost universally by scientists.
These pseudoscientific "controversies" play on the ethical fairness many of us feel, but little on logic. Sadly this trend seems to be growing and threatens to undermine science.
The 10 Commandments (according to Brother Jed)
I've mentioned a certain funadmentalist preacher by the name of Brother Jed Smock before. He tours college campus and condemns everyone to hell with his fire and brimstone preaching.
As we say in Missouri, "He's a hoot."
So much so in fact, that I tend to skip my classes to smirk at Smock. Back in 2003, he came to Missouri State University's campus (formerly Southwest Missouri State) on October 31. I was in attendence at that time and happened to catch him when he was first setting up.
I proceeded to listen to his sermons for the better part of 5 hours. In that time, he explicitly named ten things that would earn you a one way trip straight to Hell. These ten no-no's became known to my friends and I as "The Brother Jed 10 commandments" and I share them with you now (the current high score is 8.5):
Thou Shalt Not...
I. ... drink to intoxication.
II. ... hug, kiss, or have sex before marriage.
III. ... masturbate.
IV. ... listen to Rock & Roll music.
V. ... wear tight pants.
VI. ... be a lesbian (especially a communist lesbian, that's totally unforgivable/
VII. ... be a member of a fraternity or a sorority, for lo, it is worse to be in a sorority than to be a whore because at least whores get paid.*
VIII. ... get any part of your body pierced besides your ears.
IX. ... disco dance.
X. ... be a designated driver, for this is like driving the bus to Hell. **
* - This comment was made just as a Christian sorority had walked up to lend support to Brother Jed. They promptly left.
** - At this point I started a chorus of "The wheels on the Hell Bus go round and round..."
As we say in Missouri, "He's a hoot."
So much so in fact, that I tend to skip my classes to smirk at Smock. Back in 2003, he came to Missouri State University's campus (formerly Southwest Missouri State) on October 31. I was in attendence at that time and happened to catch him when he was first setting up.
I proceeded to listen to his sermons for the better part of 5 hours. In that time, he explicitly named ten things that would earn you a one way trip straight to Hell. These ten no-no's became known to my friends and I as "The Brother Jed 10 commandments" and I share them with you now (the current high score is 8.5):
Thou Shalt Not...
I. ... drink to intoxication.
II. ... hug, kiss, or have sex before marriage.
III. ... masturbate.
IV. ... listen to Rock & Roll music.
V. ... wear tight pants.
VI. ... be a lesbian (especially a communist lesbian, that's totally unforgivable/
VII. ... be a member of a fraternity or a sorority, for lo, it is worse to be in a sorority than to be a whore because at least whores get paid.*
VIII. ... get any part of your body pierced besides your ears.
IX. ... disco dance.
X. ... be a designated driver, for this is like driving the bus to Hell. **
* - This comment was made just as a Christian sorority had walked up to lend support to Brother Jed. They promptly left.
** - At this point I started a chorus of "The wheels on the Hell Bus go round and round..."
Astronomy Internship - Day 7
I woke up later than usual again today due to waking up at 4:00 in the morning and not being able to get back to sleep for over an hour.
Breakfast was decent today as I got there in time to get a waffle.
As predicted, the morning session was laid back since we'd all finished our practical exercise from yesterday on finding magnitudes for a series of stars (photometry).
For lunch I hit the Panda Express here. Quite good.
The afternoon session consisted of a rather imprompteau lesson on how to do what's known as profile fit photometry which is required when the field of stars you're looking at is sufficiently dense that the images of stars begin to overlap. This lecture was quite good. The concepts for all of this is pretty easy, but eventually I'm going to need to get a more detailed description of the actual commands that IRAF uses since this profile fit photometry is what I'm going to be doing a lot of with the cluster I'll be looking at.
And just to prove that we actually do do some work, here's a few pictures:
Because I ended up not getting my full amount of sleep, I ended up relaxing this evening and read a book. Tomorrow will consist, in part, of reading through the literature I've printed out concerning the cluster I'll be analyzing first. So expect a post tomorrow with some information about cluster NGC 7142! Exciting.
Breakfast was decent today as I got there in time to get a waffle.
As predicted, the morning session was laid back since we'd all finished our practical exercise from yesterday on finding magnitudes for a series of stars (photometry).
For lunch I hit the Panda Express here. Quite good.
The afternoon session consisted of a rather imprompteau lesson on how to do what's known as profile fit photometry which is required when the field of stars you're looking at is sufficiently dense that the images of stars begin to overlap. This lecture was quite good. The concepts for all of this is pretty easy, but eventually I'm going to need to get a more detailed description of the actual commands that IRAF uses since this profile fit photometry is what I'm going to be doing a lot of with the cluster I'll be looking at.
And just to prove that we actually do do some work, here's a few pictures:
Because I ended up not getting my full amount of sleep, I ended up relaxing this evening and read a book. Tomorrow will consist, in part, of reading through the literature I've printed out concerning the cluster I'll be analyzing first. So expect a post tomorrow with some information about cluster NGC 7142! Exciting.
Friday, June 16, 2006
Inane antics
The No Child Left Behind act was signed into law in 2002. Yet only now, 4 years later, has the government admitted that something is wrong. Yet the writing has been on the wall for a very long time it seems.
Long before Bush ever made NCLB a national campaign, it was enacted in Texas and hailed as an educational miracle. Yet the truth is very different. Schools began hiding failing students to keep from loosing funding.
Since it's inception, it has been vigorously opposed by bother the National Education Assosciation and the American Federation of Teachers.
In 2004, NCLB was failing so badly that the department of education contracted with Ketchum Inc. to promote the law. However, the advertisments were designed to come across as news stories, which drew the attention of many given that this action qualified it as propaganda, which is outlawed.
In 2005, Utah became so frustrated that governor John Huntsman signed a bill allowing schools to effectively ignore parts of the NCLB act that conflicted with the school's programs.
Additionally, hidden amongst the other mess is a section forcing schools to surrender students information to military recruiters.
The writing has been on the wall for a long time that NCLB is a failing act. Yet it seems the rule for this administration to take forever to see what many people could have pointed out long before the act was ever instituted.
Long before Bush ever made NCLB a national campaign, it was enacted in Texas and hailed as an educational miracle. Yet the truth is very different. Schools began hiding failing students to keep from loosing funding.
Since it's inception, it has been vigorously opposed by bother the National Education Assosciation and the American Federation of Teachers.
In 2004, NCLB was failing so badly that the department of education contracted with Ketchum Inc. to promote the law. However, the advertisments were designed to come across as news stories, which drew the attention of many given that this action qualified it as propaganda, which is outlawed.
In 2005, Utah became so frustrated that governor John Huntsman signed a bill allowing schools to effectively ignore parts of the NCLB act that conflicted with the school's programs.
Additionally, hidden amongst the other mess is a section forcing schools to surrender students information to military recruiters.
The writing has been on the wall for a long time that NCLB is a failing act. Yet it seems the rule for this administration to take forever to see what many people could have pointed out long before the act was ever instituted.
Astronomy Internship - Day 6
Ended up waking up a bit later than normal today. It was already 8:00 by the time I pulled myself out of bed.
As usual, breakfast wasn't very good. I grabbed french toast thinking that it couldn't be too bad. But when I sat down at the table Tiara warned me that it was supposedly stale. Poking it confirmed it. The sausage would have been good had it been warm still. So my breakfast consisted primarily of grapes.
In our morning session today, we discussed the brignesses of stars and how they're measured. The professor giving the lecture today was unusually boring. At one point, he took nearly 30 minutes to repeat a single point in several slightly different ways.
I used my lunch today at a place called Steak Escape which has Philly cheese steaks. They were quite good but could have been a bit more flavorful. I'm not sure how. Perhaps some pepper jack instead of provelone for cheese.
Then it was back to work. The afternoon session consisted of learning to use IRAF to determine a stars magnitude after correction for atmosphere. This was a simplified version of what I'll be doing for the first of my two projects. However, the project will be much more complicated. For the exercise today, the field of stars was relatively sparse, so it was easy to find a patch of sky right next to the star to determine sky brightness (I'll discuss this in more detail in one of my upcoming astronomical data posts). For my project, I'll be looking at a much denser of stars which requires more advanced methods.
Once we finished this, the group headed to the beach. On the boardwalk there were some cute cartoons in the sand:
As I walked down a bit more I found it was done by a nice old man with a broom
Eventually the sun went down and we headed back to the dorm.
To get the salt out of our hair, we all jumped in the dorm's pool with was wonderfully warm.
Tomorrow we're supposed to finish the task I think everyone finished today, so it should be pretty laid back.
As usual, breakfast wasn't very good. I grabbed french toast thinking that it couldn't be too bad. But when I sat down at the table Tiara warned me that it was supposedly stale. Poking it confirmed it. The sausage would have been good had it been warm still. So my breakfast consisted primarily of grapes.
In our morning session today, we discussed the brignesses of stars and how they're measured. The professor giving the lecture today was unusually boring. At one point, he took nearly 30 minutes to repeat a single point in several slightly different ways.
I used my lunch today at a place called Steak Escape which has Philly cheese steaks. They were quite good but could have been a bit more flavorful. I'm not sure how. Perhaps some pepper jack instead of provelone for cheese.
Then it was back to work. The afternoon session consisted of learning to use IRAF to determine a stars magnitude after correction for atmosphere. This was a simplified version of what I'll be doing for the first of my two projects. However, the project will be much more complicated. For the exercise today, the field of stars was relatively sparse, so it was easy to find a patch of sky right next to the star to determine sky brightness (I'll discuss this in more detail in one of my upcoming astronomical data posts). For my project, I'll be looking at a much denser of stars which requires more advanced methods.
Once we finished this, the group headed to the beach. On the boardwalk there were some cute cartoons in the sand:
As I walked down a bit more I found it was done by a nice old man with a broom
Eventually the sun went down and we headed back to the dorm.
To get the salt out of our hair, we all jumped in the dorm's pool with was wonderfully warm.
Tomorrow we're supposed to finish the task I think everyone finished today, so it should be pretty laid back.
Wednesday, June 14, 2006
Astronomy Internship - Day 5
It seems that in my exploring of campus yesterday I managed to get a light sunburn. Oh well. Such things happen.
Anyway, today started off sunny for a change. My roomate got up early to go to the computer lab and work on the data reduction with one of the people that was having trouble last night.
As usual, I got up shortly before 8 and took my shower before heading off to breakfast. I didn't think it was possible, but the dorm food seems to be getting worse. The scrambled eggs are generally watery and I have refused to touch them after the first day. However, the hard boiled ones aren't bad. The pancakes would have been edible if there was some decent syrup.
After breakfast, Tiara and I headed to the lab building. Our morning session was finishing up whatever we hadn't last night. Given that most of us were almost complete this wasn't hard. However, I seemingly managaed to edit some of my original files in an incorrect manner last night, so I decided to redo the entire process.
However, since I knew how everything worked this time, I was able to complete the task in just over 20 minutes instead of the nearly 2 hours I'd spent last night.
Yesterday, there had been a miscommunication about how lunch was supposed to work. However that was straigtened out today and the group ate at one of the student unions. The food there was quite excellent. Unfortunately, lunch will only be provided there until until the end of the week. After that, it will all be served from the dining halls.
Once we finished eating, a few of us headed over to the library to see if we could find any materials that would be helpful in our research. Since my topic is very narrow, books are of little use to me (I'll need mostly journal articles which I get off the web), but I went along to take a few pictures of the inside of the library.
The astronomy books were located on the top story which had a nice view:
I ended up getting lost in the oddly laid out building on my way out.
For our afternoon session, we had a lecture on the statistics important in astronomical research, especially as how they applied to determining experimental uncertainty. For the most part, it was review as we have to apply most of these methods in the physics labs I'd taken. The only really new part was what's known as Poisson distributions which gives a simple method for finding the uncertainty in a measurement when you only have one and it involves counting a number of occurances over an interval of time.
Dinner was little better than breakfast and consisted of some sort of glazed pork chop. The meat was extremely chewy and not terribly good anyway. The corn was very soggy. The best part was the mashed potatos. Can you tell I'm from the midwest?
Once dinner was over, I headed back to my room and did a bit of reading.
Anyway, today started off sunny for a change. My roomate got up early to go to the computer lab and work on the data reduction with one of the people that was having trouble last night.
As usual, I got up shortly before 8 and took my shower before heading off to breakfast. I didn't think it was possible, but the dorm food seems to be getting worse. The scrambled eggs are generally watery and I have refused to touch them after the first day. However, the hard boiled ones aren't bad. The pancakes would have been edible if there was some decent syrup.
After breakfast, Tiara and I headed to the lab building. Our morning session was finishing up whatever we hadn't last night. Given that most of us were almost complete this wasn't hard. However, I seemingly managaed to edit some of my original files in an incorrect manner last night, so I decided to redo the entire process.
However, since I knew how everything worked this time, I was able to complete the task in just over 20 minutes instead of the nearly 2 hours I'd spent last night.
Yesterday, there had been a miscommunication about how lunch was supposed to work. However that was straigtened out today and the group ate at one of the student unions. The food there was quite excellent. Unfortunately, lunch will only be provided there until until the end of the week. After that, it will all be served from the dining halls.
Once we finished eating, a few of us headed over to the library to see if we could find any materials that would be helpful in our research. Since my topic is very narrow, books are of little use to me (I'll need mostly journal articles which I get off the web), but I went along to take a few pictures of the inside of the library.
The astronomy books were located on the top story which had a nice view:
I ended up getting lost in the oddly laid out building on my way out.
For our afternoon session, we had a lecture on the statistics important in astronomical research, especially as how they applied to determining experimental uncertainty. For the most part, it was review as we have to apply most of these methods in the physics labs I'd taken. The only really new part was what's known as Poisson distributions which gives a simple method for finding the uncertainty in a measurement when you only have one and it involves counting a number of occurances over an interval of time.
Dinner was little better than breakfast and consisted of some sort of glazed pork chop. The meat was extremely chewy and not terribly good anyway. The corn was very soggy. The best part was the mashed potatos. Can you tell I'm from the midwest?
Once dinner was over, I headed back to my room and did a bit of reading.
Astronomical Data - 2b. Light Detection
In my last post on this topic we learned several challanges for light to reach us. Aside from possible interstellar clouds that obscure our signal, there's also a significant distortion and dimming from our own atmosphere. But the fun doesn't stop there!
In this post we'll explore the final step of astronomical obesrvations: the detection and the problems associated with it.
The first device used to observed starlight was undoubtedly the human eye. In some ways this tool is far superior than any other in use today, yet in many others, is extremely difficult.
Around 150BC, Hipparchus, a greek astronomer, developed a system using the unaided human eye in which he classified the brightness of stars. The system places stars in categories called magnitudes. Brightest stars he gave a magnitude of 1. The faintest he could observe he gave a magnitude of 7.
Surprisingly, the human eye works well at determining what category stars should be placed into. The problem with this system is that the human eye doesn't work linearly. That means that if star A is twice as bright as star B, then the human eye doesn't actually A as twice as bright as B. The reason for this is that the human eye uses a logrithmic scale. Accordingly, the magnitude scale is logrithmic as well, making the system rather difficult.
The magnitude system is even more frustrating when you stop to consider that it runs backwards! Bright stars are smaller numbers. Thus, when you graph things using the magnitude system, you generally have to flip the Y axis over. Over time, revisions were done to the magnitude system so that there was a strict mathematical definition of magnitudes. However, it still remains largely the same.
This standard of naked eye observing was common for many centuries. During the Middle Ages, calls for astronomical predictions increased, and astrologers (the forerunners of astronomy) began developing new instruments to more accurately measure the position of stars and planets.
One important person amongst these people was Tycho Brahe who was an extremely interesting character. Apparently he was a rather convivial fellow who enjoyed drinking and dueling. In fact, he had at some point lost his nose in a duel and had it replaced with a brass one.
Legend has long held that Brahe met his death thanks to his other addiction. During a dinner with royalty in Prague in 1601, he supposedly drank too much. Yet due to the rules of ettiquite, he was not allowed to leave the table until the host left. After drinking too much wine, his bladder eventually burst. However, more recent investigations have shown that he most likely died of mercury poisoning.
Yet although his lifestyle was unconventional, he did make excellent contributions to astronomy. His observatory housed large sextants with which he could measure the position of celestial objects to far greater position than any other at the time. Amongst his discoveries was the discovery of a "novae", or "new star" in Cassiopiea. This destroyed the long held belief that the heavens were static and unchanging.
However, Tycho did not release his data. Upon his death, his apprentice Johannes Kepler used his data to lend strong support to the heliocentric model.
The next major revolution came with the development of the telescope. Although its development is generally attributed to Galileo, this is incorrect. The telescope had already been in existance, but Galileo made several improvements and was the first to make recorded astronomical observations using it. Among them was the realization that there were many small craters on the moon as well as stars too faint to see to the unaided eye.
For many years, observations were done by hand:
This continued until the invention of photographic film the mid 1800's. This allowed for major revolutions in the astronomical field. The main advantage that film has over the human eye, is the ablility to do long exposures, and thus, bring out detail that would otherwise be lost.
New nebulae that were far too faint to see even with powerful telescopes were suddenly discovered as well as millions of new stars. Photographic film is also very useful because it allows for very large fields of view.
However, photographic film wasn't without problems. One of the largest was a property known as the "quantum efficiency". Don't be intimidated by the big word. It really just means what percentage of incoming light is actually turned into an image. With standard photographic film today, less than 5% of light that falls on the film actually goes towards making the image.
For standard use everyday, this isn't a problem because there's millions of photons streaming into your camera. However, when every photon is precious, only getting a few precent is a sore deal. Eventually, techniques were developed that increased the quantum efficiency to closer to 10%. But these techniques were difficult and extremely expensive.
Due to the poor light sensitivity, this means that exposure times will have to be relatively long. Since the Earth is constantly turning, this means that the telescope will have to track the night sky perfectly, until the image is finished.
Another problem with film is that its quantum efficiency is different at different wavelengths. Thus, film was great for making pretty pictures, but made extracting numerical data extremely difficult.
Similar to the human eye, photographic film is also non-linear. For certain brightnesses, it performs quite well, but after a certain point, no matter how much you increase the light falling on a given part of the film, the image will not appear any brighter in the result. Again, this non-linearity makes extracting data difficult.
By the 1970's a new type of device known as a Charge Couple Device (CCD). These are the receptors used in most digital cameras today. One of the largest advantages of CCDs is that they have extremely high quantum efficiency. Even a cheap CCD will often be above 60%. The tens to hundred of dollar astronomical grade CCDs will have quantum efficiencies of closer to 90%! Higher quantum efficiency means less exposure times which means its easier to track, as well as the ability to do more science in one night!
Another major advantage is that CCD cameras are very linear! Doubling the brightness of an object doubles the output value the computer reads out.
So what are the disadvantages?
One of the main ones is that CCDs are very expensive. This stems from the fact that they're also very hard to produce. The difficulty in producing them leads to small sizes. Thus, only images of small sections of sky can be taken. To solve this problem, several CCDs can be gluded together side by side. But if one CCD is expensive, an array is even worse.
The next is that CCDs take a long time to "read out". This means that getting the image from the CCD camera onto a computer takes quite awhile in comparison to film which is just a sort of *snap* next frame. If you've ever downloaded a full resolution image from a digital camera to your computer, you'll know that this can take a few seconds. However, because of how CCDs work, astronomical CCDs take even longer because we're worried about preserving every bit of data. Additionally, the images for astronomical CCDs are much larger in size than those for a digital camera.
Lastly, CCDs are very "noisy". To explain this problem, we'll have to first take a look at how CCDs work.
A CCD in essence is just a very large grid of (generally) silicon. When a photon comes and hits an atom in one of the boxes in the grid, it will knock off an electron. Thus, that box will have an electron floating in it. The more photons strike a box, the more free electrons.
Once the exposure is done, the CCD counts how many electrons are in each box. The number is then displayed on a computer as a brightness of that box.
One of the problems with this is that, to read how many electrons are in each box, the box must move to the counter. If we're not careful, electrons can spill out during this process, hence the reason astronomical CCDs move the boxes slowly where digital cameras run the boxes over as fast as they can.
However, photons hitting the silicon isn't the only way to get an electron. On a microscopic level, atoms are always bouncing around. The hotter something is, the more they bounce. Occasionally, when two atoms bump into one another, this collision will knock off an electron. The result of this is an extra electron that looks like it came from a photon, when in reality, it had nothing to do with it. This sort of noise is called a "dark current" since the CCD will read like it's getting light even when the shutter is closed.
Another source of noise is what's called "bias". If a CCD were cleared and then immediately read out without having any exposure time, it would still read some signal just due to electronic circuits not being perfect.
The third source of error in CCDs is imperfections in the equipment. When making CCDs, it's impossible to make each of the boxes the exact same size given that each box is only a few microns across. Inherently, if one box is larger than the one next to it, it will collect more photons than its dimunitive neighbor. However, when displayed on your computer, each pixel on your monitor is the same size. Thus, the pixel corresponding to the smaller box will be darker than it should be if the boxes on the CCD were perfect, while the bigger boxed pixel will appear brighter.
Additionally, problems in the equipment arise due to dust in the optics. Dust will cast a shadow onto the CCD. Since the dust is out of focus, this will cause it to appear as a darkened doughnut shape on the image.
So by this point, we have gas and dust in space blocking light, our atmosphere absorbing and blurring the light, the CCDs reading non-existant light as well as unevenly distributing what light it finally recieves...
How do we ever get anything useful!?
I'll explore how astronomers can correct for many of these problems in my next post in this topic.
How's that for a cliffhanger?
In this post we'll explore the final step of astronomical obesrvations: the detection and the problems associated with it.
The first device used to observed starlight was undoubtedly the human eye. In some ways this tool is far superior than any other in use today, yet in many others, is extremely difficult.
Around 150BC, Hipparchus, a greek astronomer, developed a system using the unaided human eye in which he classified the brightness of stars. The system places stars in categories called magnitudes. Brightest stars he gave a magnitude of 1. The faintest he could observe he gave a magnitude of 7.
Surprisingly, the human eye works well at determining what category stars should be placed into. The problem with this system is that the human eye doesn't work linearly. That means that if star A is twice as bright as star B, then the human eye doesn't actually A as twice as bright as B. The reason for this is that the human eye uses a logrithmic scale. Accordingly, the magnitude scale is logrithmic as well, making the system rather difficult.
The magnitude system is even more frustrating when you stop to consider that it runs backwards! Bright stars are smaller numbers. Thus, when you graph things using the magnitude system, you generally have to flip the Y axis over. Over time, revisions were done to the magnitude system so that there was a strict mathematical definition of magnitudes. However, it still remains largely the same.
This standard of naked eye observing was common for many centuries. During the Middle Ages, calls for astronomical predictions increased, and astrologers (the forerunners of astronomy) began developing new instruments to more accurately measure the position of stars and planets.
One important person amongst these people was Tycho Brahe who was an extremely interesting character. Apparently he was a rather convivial fellow who enjoyed drinking and dueling. In fact, he had at some point lost his nose in a duel and had it replaced with a brass one.
Legend has long held that Brahe met his death thanks to his other addiction. During a dinner with royalty in Prague in 1601, he supposedly drank too much. Yet due to the rules of ettiquite, he was not allowed to leave the table until the host left. After drinking too much wine, his bladder eventually burst. However, more recent investigations have shown that he most likely died of mercury poisoning.
Yet although his lifestyle was unconventional, he did make excellent contributions to astronomy. His observatory housed large sextants with which he could measure the position of celestial objects to far greater position than any other at the time. Amongst his discoveries was the discovery of a "novae", or "new star" in Cassiopiea. This destroyed the long held belief that the heavens were static and unchanging.
However, Tycho did not release his data. Upon his death, his apprentice Johannes Kepler used his data to lend strong support to the heliocentric model.
The next major revolution came with the development of the telescope. Although its development is generally attributed to Galileo, this is incorrect. The telescope had already been in existance, but Galileo made several improvements and was the first to make recorded astronomical observations using it. Among them was the realization that there were many small craters on the moon as well as stars too faint to see to the unaided eye.
For many years, observations were done by hand:
This continued until the invention of photographic film the mid 1800's. This allowed for major revolutions in the astronomical field. The main advantage that film has over the human eye, is the ablility to do long exposures, and thus, bring out detail that would otherwise be lost.
New nebulae that were far too faint to see even with powerful telescopes were suddenly discovered as well as millions of new stars. Photographic film is also very useful because it allows for very large fields of view.
However, photographic film wasn't without problems. One of the largest was a property known as the "quantum efficiency". Don't be intimidated by the big word. It really just means what percentage of incoming light is actually turned into an image. With standard photographic film today, less than 5% of light that falls on the film actually goes towards making the image.
For standard use everyday, this isn't a problem because there's millions of photons streaming into your camera. However, when every photon is precious, only getting a few precent is a sore deal. Eventually, techniques were developed that increased the quantum efficiency to closer to 10%. But these techniques were difficult and extremely expensive.
Due to the poor light sensitivity, this means that exposure times will have to be relatively long. Since the Earth is constantly turning, this means that the telescope will have to track the night sky perfectly, until the image is finished.
Another problem with film is that its quantum efficiency is different at different wavelengths. Thus, film was great for making pretty pictures, but made extracting numerical data extremely difficult.
Similar to the human eye, photographic film is also non-linear. For certain brightnesses, it performs quite well, but after a certain point, no matter how much you increase the light falling on a given part of the film, the image will not appear any brighter in the result. Again, this non-linearity makes extracting data difficult.
By the 1970's a new type of device known as a Charge Couple Device (CCD). These are the receptors used in most digital cameras today. One of the largest advantages of CCDs is that they have extremely high quantum efficiency. Even a cheap CCD will often be above 60%. The tens to hundred of dollar astronomical grade CCDs will have quantum efficiencies of closer to 90%! Higher quantum efficiency means less exposure times which means its easier to track, as well as the ability to do more science in one night!
Another major advantage is that CCD cameras are very linear! Doubling the brightness of an object doubles the output value the computer reads out.
So what are the disadvantages?
One of the main ones is that CCDs are very expensive. This stems from the fact that they're also very hard to produce. The difficulty in producing them leads to small sizes. Thus, only images of small sections of sky can be taken. To solve this problem, several CCDs can be gluded together side by side. But if one CCD is expensive, an array is even worse.
The next is that CCDs take a long time to "read out". This means that getting the image from the CCD camera onto a computer takes quite awhile in comparison to film which is just a sort of *snap* next frame. If you've ever downloaded a full resolution image from a digital camera to your computer, you'll know that this can take a few seconds. However, because of how CCDs work, astronomical CCDs take even longer because we're worried about preserving every bit of data. Additionally, the images for astronomical CCDs are much larger in size than those for a digital camera.
Lastly, CCDs are very "noisy". To explain this problem, we'll have to first take a look at how CCDs work.
A CCD in essence is just a very large grid of (generally) silicon. When a photon comes and hits an atom in one of the boxes in the grid, it will knock off an electron. Thus, that box will have an electron floating in it. The more photons strike a box, the more free electrons.
Once the exposure is done, the CCD counts how many electrons are in each box. The number is then displayed on a computer as a brightness of that box.
One of the problems with this is that, to read how many electrons are in each box, the box must move to the counter. If we're not careful, electrons can spill out during this process, hence the reason astronomical CCDs move the boxes slowly where digital cameras run the boxes over as fast as they can.
However, photons hitting the silicon isn't the only way to get an electron. On a microscopic level, atoms are always bouncing around. The hotter something is, the more they bounce. Occasionally, when two atoms bump into one another, this collision will knock off an electron. The result of this is an extra electron that looks like it came from a photon, when in reality, it had nothing to do with it. This sort of noise is called a "dark current" since the CCD will read like it's getting light even when the shutter is closed.
Another source of noise is what's called "bias". If a CCD were cleared and then immediately read out without having any exposure time, it would still read some signal just due to electronic circuits not being perfect.
The third source of error in CCDs is imperfections in the equipment. When making CCDs, it's impossible to make each of the boxes the exact same size given that each box is only a few microns across. Inherently, if one box is larger than the one next to it, it will collect more photons than its dimunitive neighbor. However, when displayed on your computer, each pixel on your monitor is the same size. Thus, the pixel corresponding to the smaller box will be darker than it should be if the boxes on the CCD were perfect, while the bigger boxed pixel will appear brighter.
Additionally, problems in the equipment arise due to dust in the optics. Dust will cast a shadow onto the CCD. Since the dust is out of focus, this will cause it to appear as a darkened doughnut shape on the image.
So by this point, we have gas and dust in space blocking light, our atmosphere absorbing and blurring the light, the CCDs reading non-existant light as well as unevenly distributing what light it finally recieves...
How do we ever get anything useful!?
I'll explore how astronomers can correct for many of these problems in my next post in this topic.
How's that for a cliffhanger?
Tuesday, June 13, 2006
DI Desperate for SETI
One of Dembski's favourite claims is that ID's attempt to discover intelligence is legitimate because SETI, which is widely held to do legitimate science, is also looking for intelligence.
To be able to support this claim, Dembski must attempt to prove that both he and SETI use the same sorts of methodology to complete their ivestigations.
In a recent post in his blog Dembski makes a pathetic and desperate attempt to conflate the two.
He cites a Physics Today article which says that SETI has begun searching for extremely bright and narrow beams of light, which cannot be produced by any known astronomical sources.
Dembski says this is the same as his "explanatory filter" which seeks to eliminate possibilities of chance and nature producing observed effects. However, even in the material Dembski quotes, we can see striking differences that Dembski has had to overlook in order to rationalize the differences between the two fields away so that he may pretend that what he is doing has merit.
The first thing he overlooks is that the article mentions that it does not conclusively rule out astronomical sources.
What this reveals is that Dembski has no interest in using the scientific method in which things must be reexamined. Instead he washes his hands of the process as soon as he gets a result which he likes, refusing to accept that there is any other possibility.
In responding to a comment left, Dembski's faithful hound, Dave Scott, claims to have insight into how intelligent beings will attempt to communicate:
This bias is not one that SETI accepts. Because SETI realizes that its impossible for us to know the data format of an alien race, we should not expect to find a "message in a bottle". Instead of finding something complex that we may not recognize and just pass over as astronomical noise, SETI instead looks for extremely simple and unmistakable patterns that do not rely on language, culture, or any other preconcieved notions. This is why things like sequences of prime numbers work exceptionally well.
One of the later posters responds to DaveScott's egregarious comment and points out that, when one reads the full article (which Dembski apparently didn't read even though most universities provide free online subscriptions to such publications), SETI explicitly states that they do not seek the "phase-encoded messageing one seeks with radio-telescope".
Once again the DI's sloppy academics and desperate attempts for legitimacy have fallen flat.
To be able to support this claim, Dembski must attempt to prove that both he and SETI use the same sorts of methodology to complete their ivestigations.
In a recent post in his blog Dembski makes a pathetic and desperate attempt to conflate the two.
He cites a Physics Today article which says that SETI has begun searching for extremely bright and narrow beams of light, which cannot be produced by any known astronomical sources.
Dembski says this is the same as his "explanatory filter" which seeks to eliminate possibilities of chance and nature producing observed effects. However, even in the material Dembski quotes, we can see striking differences that Dembski has had to overlook in order to rationalize the differences between the two fields away so that he may pretend that what he is doing has merit.
The first thing he overlooks is that the article mentions that it does not conclusively rule out astronomical sources.
If it’s not from an alien civilization, at least we will have discovered an astrophysical phenomenon that no one anticipated. Not a bad consolation prize.So what's the difference here? With Dembski, he can't explain it and it passes through his filter. Thus it must be design. With SETI, they can't explain it, so it bears further investigation. Thus it may be design, or it may be an "astrophysical phenomenon".
What this reveals is that Dembski has no interest in using the scientific method in which things must be reexamined. Instead he washes his hands of the process as soon as he gets a result which he likes, refusing to accept that there is any other possibility.
In responding to a comment left, Dembski's faithful hound, Dave Scott, claims to have insight into how intelligent beings will attempt to communicate:
Any technological entity capable of generating high power nanosecond laser pulses is going to encode a message of some sort in a stream of pulses. (Emphasis added)From this we see that the ID proponent's frequent claim that it's impossible to know the identity, motives, or methods of a designer, are all just fluff. Dave Scott clearly states that he's able to predict exactly how an alien race would communicate.
This bias is not one that SETI accepts. Because SETI realizes that its impossible for us to know the data format of an alien race, we should not expect to find a "message in a bottle". Instead of finding something complex that we may not recognize and just pass over as astronomical noise, SETI instead looks for extremely simple and unmistakable patterns that do not rely on language, culture, or any other preconcieved notions. This is why things like sequences of prime numbers work exceptionally well.
One of the later posters responds to DaveScott's egregarious comment and points out that, when one reads the full article (which Dembski apparently didn't read even though most universities provide free online subscriptions to such publications), SETI explicitly states that they do not seek the "phase-encoded messageing one seeks with radio-telescope".
Once again the DI's sloppy academics and desperate attempts for legitimacy have fallen flat.
Astronomy Internship - Day 4
Generally my sleep schedule adjust itself relatively quickly and I'm up till 2am and sleeping until 10. However, I still haven't been able to get myself on Pacific Time and still about two hours ahead. So I've been going to sleep closer to 11pm and waking up between 7 and 8.
That was a good thing today given that the fire alarm went off at a quarter till 8 in the dorm we're living in. So at least I was awake. Unfortunately, I was in the shower.
So after jumping out quickly and tossing some clothes on, I headed outside to join everyone else. As anticipated, it was a false alarm. But since it was almost 8 by the time we were let back in, we all just headed to the dining hall.
I've decided that, should my sleep schedule get adjusted, I wouldn't mind missing the breakfasts here. I'm relatively certain that their scrambled eggs are of the carton variety and probably contain little to no real egg. Additionally they're quite often watery which does not go well with my stomach. While I generally like a good amount of fat in my bacon, since that's where the flavor is, I don't much like it when it's all fat. The sausage wasn't too bad, although dry and somehow grainy. The french toast yesterday was good though. I would really just like a bagel and some cream cheese though.
After breakfast, I had a bit more free time and then it was off to learning.
This is the building it appears I'll be spending the large majority of the time in. It's about a 15 minute walk from the dorm I'm staying in, but isn't hard to find. Gee, I wonder why:
In our morning session, we got a crash course in the workings and calibrations needed for CCD imagery in Astronomy. I had a course in this 2 years ago, so it was mostly a refresher for me. It's also what I'll be discussing in my next Astronomical Data post.
Lunch wasn't provided for us today, so I instead walked around the campus and enjoyed the scenery:
The library is one of the stranger buildings on campus it appears. From what I'm told, this glass atrium is the main entrance. It goes a few stories underground, only to come back up in the building you see behind it and to the right.
The campus also has some amazing landscaping and interesting plants:
I also found some new friends:
Heading back towards the astronomy building, there's a very nice sundial at the end of one of the main campus walkways:
While I didn't spend the time to completely figure out the sundial, I do like how the shadow of the sun clearly falls on the curved line that represents the Ecliptic.
I then saw a few of the other people in the program playing with Chinese yo-yos (also known as Diablos). This is Brendan:
He's quite skilled with it and extremely impressive.
This guy is another person in the program that before today, had never tried using one of these (his name escapes me at the moment). He seemed to pick it up quite quickly and after about 20 minutes of playing with it, he and Brendan were able to sucessfully able to pass Diablos between one another:
Then it was back to work. Now we had to put what we'd learned to use on some data taken at Mount Laguna Observatory (MLO) last summer on July 4th when NASA crashed a massive probe into comet Tempel1 (!hy? To see if it had a cream filling of course).
I'll leave the details in the process to my next post on astronomical data, but it took about 2 hours worth of work to calibrate 5 images (although closer to 50 were used in the entire process as you'll understand when I make my next post).
Once we finished for the day, Dr. Sandquist (the head of the program) let us into the school's planetarium. For an antique, it was still pretty impressive.
Dinner was next up on the schedule. Afterwards, most of us headed back to the dorm for a few games of pool and foosball. At 8:00 six of the ten people in the program went back to the astronomy building and crunched more data for another set of images that we'll be working with tomorrow afternoon.
Fortunately, the processs went much smoother this time. Sadly though, something seemed to go wrong on the last step for a few of us, and no one could figure out why. Thus, we decided to leave it till tomorrow morning and ask one of our supervisors.
There's Brendan and Tiara trying to figure out one of the data reduction processes in IRAF.
Once we all finished and/or gave up, we headed back to the dorms again and I played Dance Dance Revolution with Brendan and Tiara in their room for a few hours and headed to bed.
That was a good thing today given that the fire alarm went off at a quarter till 8 in the dorm we're living in. So at least I was awake. Unfortunately, I was in the shower.
So after jumping out quickly and tossing some clothes on, I headed outside to join everyone else. As anticipated, it was a false alarm. But since it was almost 8 by the time we were let back in, we all just headed to the dining hall.
I've decided that, should my sleep schedule get adjusted, I wouldn't mind missing the breakfasts here. I'm relatively certain that their scrambled eggs are of the carton variety and probably contain little to no real egg. Additionally they're quite often watery which does not go well with my stomach. While I generally like a good amount of fat in my bacon, since that's where the flavor is, I don't much like it when it's all fat. The sausage wasn't too bad, although dry and somehow grainy. The french toast yesterday was good though. I would really just like a bagel and some cream cheese though.
After breakfast, I had a bit more free time and then it was off to learning.
This is the building it appears I'll be spending the large majority of the time in. It's about a 15 minute walk from the dorm I'm staying in, but isn't hard to find. Gee, I wonder why:
In our morning session, we got a crash course in the workings and calibrations needed for CCD imagery in Astronomy. I had a course in this 2 years ago, so it was mostly a refresher for me. It's also what I'll be discussing in my next Astronomical Data post.
Lunch wasn't provided for us today, so I instead walked around the campus and enjoyed the scenery:
The library is one of the stranger buildings on campus it appears. From what I'm told, this glass atrium is the main entrance. It goes a few stories underground, only to come back up in the building you see behind it and to the right.
The campus also has some amazing landscaping and interesting plants:
I also found some new friends:
Heading back towards the astronomy building, there's a very nice sundial at the end of one of the main campus walkways:
While I didn't spend the time to completely figure out the sundial, I do like how the shadow of the sun clearly falls on the curved line that represents the Ecliptic.
I then saw a few of the other people in the program playing with Chinese yo-yos (also known as Diablos). This is Brendan:
He's quite skilled with it and extremely impressive.
This guy is another person in the program that before today, had never tried using one of these (his name escapes me at the moment). He seemed to pick it up quite quickly and after about 20 minutes of playing with it, he and Brendan were able to sucessfully able to pass Diablos between one another:
Then it was back to work. Now we had to put what we'd learned to use on some data taken at Mount Laguna Observatory (MLO) last summer on July 4th when NASA crashed a massive probe into comet Tempel1 (!hy? To see if it had a cream filling of course).
I'll leave the details in the process to my next post on astronomical data, but it took about 2 hours worth of work to calibrate 5 images (although closer to 50 were used in the entire process as you'll understand when I make my next post).
Once we finished for the day, Dr. Sandquist (the head of the program) let us into the school's planetarium. For an antique, it was still pretty impressive.
Dinner was next up on the schedule. Afterwards, most of us headed back to the dorm for a few games of pool and foosball. At 8:00 six of the ten people in the program went back to the astronomy building and crunched more data for another set of images that we'll be working with tomorrow afternoon.
Fortunately, the processs went much smoother this time. Sadly though, something seemed to go wrong on the last step for a few of us, and no one could figure out why. Thus, we decided to leave it till tomorrow morning and ask one of our supervisors.
There's Brendan and Tiara trying to figure out one of the data reduction processes in IRAF.
Once we all finished and/or gave up, we headed back to the dorms again and I played Dance Dance Revolution with Brendan and Tiara in their room for a few hours and headed to bed.
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