This one's a bit backwards, but atheist sees nothing in his toast.
Astounding!
Thursday, August 07, 2008
Wednesday, July 30, 2008
Pareidolia: n + 13
Jeebus is back! And this time, he's furrier than ever.
MEOW.
Sadly, this cat's got nothin on Foobie Jesus.
MEOW.
Sadly, this cat's got nothin on Foobie Jesus.
Monday, July 21, 2008
Got a live one!
Some crazy creationist is making silly claims in the comments on this old thread. He's getting spanked pretty bad for not having read my intro to astronomy series.
So grab some popcorn and go point and laugh.
So grab some popcorn and go point and laugh.
Wednesday, July 16, 2008
Carnival of Space #63
Welcome to the 63rd carnival of space! For those that have never stopped by my corner of the web (as this is my first time hosting the carnival), thanks for stopping by.
It looks like the list of fun things is somewhat longer than normal this week! Must be a full moon...
Anyway, let's get started!
Over at a Babe in the Universe, L. Riofrio discusses the recent announcement concerning water on the moon.
At Cumbrian Sky, we hear about how the new Pheonix lander is stealing the glory from the plucky Opportunity rover while Wall*E dazzles audiences in theaters. Oh the humanity! Er... Robot-anity.
We get the recipe for a planet over at the Martian Chronicles. A little late for Fourth of July barbecues, but tasty none-the-less.
Astroblogger, Ian Musgrave, gives us his account of an occultation he observed, complete with pictures. Quite impressive for a camera simply held to the eyepiece.
Catholic Sensibity brings us the story of the discovery of new worlds and the difficulty of translating anagrams.
At the astroengine, we learn about how astronomers are working to make observations to confirm the idea that two black holes can recoil.
We also learn about a new technique of reducing the Casimir force by 30-40%.
Irene Klotz at Free Space discusses concerns at NASA about our partners in space for the ISS bringing along uninvited guests.
The question of how humans could potentially travel to and colonize new solar systems if we end up making our own inhospitable is answered at Stars With a Bang.
And speaking of going upwards and outwards, Out of the Cradle discusses the Lunar Challenge. Of course the trip isn't going to be a short one, so he also discusses some lunar literature.
Or if you want to be lazy and listen instead of reading, you can always pick up a podcast. Fortunately, the newest one is available from sky at night (warning, MP3 link. Click to stream. Right-Click > Save as to download).
But if podcasts aren't your bag, then try visiting Space Disco who writes about a children's contest to sing about the Mars lander.
Of course, this is all assuming we can even find somewhere to go. Centauri Dreams spills some cold water on our dreams, telling us planets may not be as likely to form in the first place around Centauri A.
Since my lease on my apartment is about to expire here, I've been concerned with how I'm going to get my junk a few miles down the road. What a trifling concern that is compared to getting it to even a new civilization even as close as the moon. Fortunately, at Colony Worlds, we hear about a Romanian team is looking to make small package delivery to the moon possible. I think I'll be sticking to U-haul for me though.
Meanwhile, we needn't always go elsewhere. It's always possible that space creatures could visit us.
These invaders would probably come in the form of creepy crawly little creatures because so many of them are so robust. At Twisted Physics, Jennifer Oulette tells us about some of these creatures on Earth.
But, if you don't like the idea of even having to go anywhere, Music of the Spheres tells us about an add-on for Orbiter that allows you to recreate the 2001: A Space Odyssey world.
Another alternative is just to sit back and read about how great explorations really work with other people. Far less sarlaacs and rakes that way.
At the Kentucky Space blog, we hear about students doing science! How absurd!
Pretty (noctilucent) clouds are the topic at visual astronomy.
Ever wonder what all those crazy astronomical acronyms mean? Simostronomy gives us the answer.
Interested in making pretty pictures from raw astronomical images? Then check out this post at Artsnova on using Photoshop to combine filtered images.
Adding more fuel to the fire on the naming kerfuffle, the CCSSC writes about yet another dwarf planet recently discovered. Yeah, astronomy's messy and confusing sometimes.
Another example of this confusing nature is NGC 6791, a cluster that has three different ages depending on what you're looking at.
At Altair IV, we get a view into the dungeon the blogger has been working in to sort historical space records with a view to his future and an open invitation. Additionally, he blogs about using lunar regolith as a propellant.
Whew! That was a lot of linking! Get to reading!
Carnival of Space #62 | Archive
It looks like the list of fun things is somewhat longer than normal this week! Must be a full moon...
Anyway, let's get started!
Over at a Babe in the Universe, L. Riofrio discusses the recent announcement concerning water on the moon.
At Cumbrian Sky, we hear about how the new Pheonix lander is stealing the glory from the plucky Opportunity rover while Wall*E dazzles audiences in theaters. Oh the humanity! Er... Robot-anity.
We get the recipe for a planet over at the Martian Chronicles. A little late for Fourth of July barbecues, but tasty none-the-less.
Astroblogger, Ian Musgrave, gives us his account of an occultation he observed, complete with pictures. Quite impressive for a camera simply held to the eyepiece.
Catholic Sensibity brings us the story of the discovery of new worlds and the difficulty of translating anagrams.
At the astroengine, we learn about how astronomers are working to make observations to confirm the idea that two black holes can recoil.
We also learn about a new technique of reducing the Casimir force by 30-40%.
Irene Klotz at Free Space discusses concerns at NASA about our partners in space for the ISS bringing along uninvited guests.
The question of how humans could potentially travel to and colonize new solar systems if we end up making our own inhospitable is answered at Stars With a Bang.
And speaking of going upwards and outwards, Out of the Cradle discusses the Lunar Challenge. Of course the trip isn't going to be a short one, so he also discusses some lunar literature.
Or if you want to be lazy and listen instead of reading, you can always pick up a podcast. Fortunately, the newest one is available from sky at night (warning, MP3 link. Click to stream. Right-Click > Save as to download).
But if podcasts aren't your bag, then try visiting Space Disco who writes about a children's contest to sing about the Mars lander.
Of course, this is all assuming we can even find somewhere to go. Centauri Dreams spills some cold water on our dreams, telling us planets may not be as likely to form in the first place around Centauri A.
Since my lease on my apartment is about to expire here, I've been concerned with how I'm going to get my junk a few miles down the road. What a trifling concern that is compared to getting it to even a new civilization even as close as the moon. Fortunately, at Colony Worlds, we hear about a Romanian team is looking to make small package delivery to the moon possible. I think I'll be sticking to U-haul for me though.
Meanwhile, we needn't always go elsewhere. It's always possible that space creatures could visit us.
These invaders would probably come in the form of creepy crawly little creatures because so many of them are so robust. At Twisted Physics, Jennifer Oulette tells us about some of these creatures on Earth.
But, if you don't like the idea of even having to go anywhere, Music of the Spheres tells us about an add-on for Orbiter that allows you to recreate the 2001: A Space Odyssey world.
Another alternative is just to sit back and read about how great explorations really work with other people. Far less sarlaacs and rakes that way.
At the Kentucky Space blog, we hear about students doing science! How absurd!
Pretty (noctilucent) clouds are the topic at visual astronomy.
Ever wonder what all those crazy astronomical acronyms mean? Simostronomy gives us the answer.
Interested in making pretty pictures from raw astronomical images? Then check out this post at Artsnova on using Photoshop to combine filtered images.
Adding more fuel to the fire on the naming kerfuffle, the CCSSC writes about yet another dwarf planet recently discovered. Yeah, astronomy's messy and confusing sometimes.
Another example of this confusing nature is NGC 6791, a cluster that has three different ages depending on what you're looking at.
At Altair IV, we get a view into the dungeon the blogger has been working in to sort historical space records with a view to his future and an open invitation. Additionally, he blogs about using lunar regolith as a propellant.
Whew! That was a lot of linking! Get to reading!
Friday, July 11, 2008
The Eucharist Challenge
Over at the atheism livejournal group, user mothwentbad poses a challenge in response to the Catholic League's response to PZ's recent guffaw.
Bill Donahue, writing in response to PZ, said,
Before even reading the other responses, I sure thought of something that I'd consider far worse. Perhaps molesting children and then covering it up. Repeatedly.
Damn. That really wasn't hard.
Bill Donahue, writing in response to PZ, said,
It is hard to think of anything more vile than to intentionally desecrate the Body of Christ.So mothwentbad asked the question: Can you think of something worse?
Before even reading the other responses, I sure thought of something that I'd consider far worse. Perhaps molesting children and then covering it up. Repeatedly.
Damn. That really wasn't hard.
Wednesday, July 09, 2008
Star Wars > Biology
Over in the UK, more kids can identify Yoda than they can an oak leaf or a magpie. I'd be quite surprised if the same weren't true for the US as well.
In reality, this isn't surprising. It's not a matter of, "the virtual world ... winning." I strongly suspect that about the same number of kids could also identify Paris Hilton, and other people that aren't at all important in their lives. We're programmed to remember people (or in this case anthropomorphized aliens) much better than mundane objects.
But we'll just let the biologists have their good cry over it. There there. We still love you even if you can't defeat a Dark Lord of the Sith.
In reality, this isn't surprising. It's not a matter of, "the virtual world ... winning." I strongly suspect that about the same number of kids could also identify Paris Hilton, and other people that aren't at all important in their lives. We're programmed to remember people (or in this case anthropomorphized aliens) much better than mundane objects.
But we'll just let the biologists have their good cry over it. There there. We still love you even if you can't defeat a Dark Lord of the Sith.
Good Job Russia!
All over the world, psychics, spiritualists, and other cons claiming to have supernatural powers get away with taking in the gullible. But it looks like Russia has put a stop to at least one of them. The story tells that Grigory Grabovoy scammed people into thinking that he could raise the dead if they just paid him enough money (the equivalent of a few thousand dollars).
He gets 11 years in prison for his scam.
Obviously his lawyers don't think it's fair, saying, "We think the sentence is based on speculation and is absolutely unfair."
Speculation? Someone taking money for services that I damn well bet he hasn't performed is speculation? ROFL!
Good job Russia!
He gets 11 years in prison for his scam.
Obviously his lawyers don't think it's fair, saying, "We think the sentence is based on speculation and is absolutely unfair."
Speculation? Someone taking money for services that I damn well bet he hasn't performed is speculation? ROFL!
Good job Russia!
Tuesday, July 08, 2008
Flare Research: Evidence just keeps on comin...
I haven't been working on the research I started last semester this summer (although I intend to get back to it when I really get settled with everything else going on). However, there's other groups out there working on the same issue.
Today a new paper popped up on the pre-print server.
One of the predictions that the original paper we were basing our work off of said that, if planets could induce massive flares, we should see enhanced X-ray activity on stars with close in planets.
This isn't a 100% sign that the planets could induce as massive of flares as the ones we're interested in, but it's one of the necessary conditions that had better be confirmed.
So this group at Harvard took a look at the amount of X-rays coming from 230 stars. And what did they find?
Well, not just yet. Like all good scientists, these guys looked at possible sources or error and bias. And the word on that one?
Yep. And what's more, after some modeling, they found that the enhancement may be be dependent on the simple multiple of the fields (the planet's and the star's). Thus, if we know the magnetic field of the star, we may be able to start probing the magnetic fields of planets for the first time.
Pretty cool.
Today a new paper popped up on the pre-print server.
One of the predictions that the original paper we were basing our work off of said that, if planets could induce massive flares, we should see enhanced X-ray activity on stars with close in planets.
This isn't a 100% sign that the planets could induce as massive of flares as the ones we're interested in, but it's one of the necessary conditions that had better be confirmed.
So this group at Harvard took a look at the amount of X-rays coming from 230 stars. And what did they find?
invariably the close-in samples have X-ray luminosities higher than that of the distant sample.Horay! Prediction verified! Right?
Well, not just yet. Like all good scientists, these guys looked at possible sources or error and bias. And the word on that one?
observational biases account for about half of the observed differences seen in the data.Eep! Ok. But if half the data isn't helpful, is the other half still good enough?
Yep. And what's more, after some modeling, they found that the enhancement may be be dependent on the simple multiple of the fields (the planet's and the star's). Thus, if we know the magnetic field of the star, we may be able to start probing the magnetic fields of planets for the first time.
Pretty cool.
Monday, July 07, 2008
Bigger and Better
A long time ago I had a post on raw images in astronomy are turned into usable data followed by another on how those are turned into pretty pictures.
I did my best to provide some pictures to illustrate what I was talking about, but they weren't anything exciting. What would be really exciting is if you could see this for something really cool. Like a Hubble image.
Turns out, you can! PBS put together a wonderful little flash on how the amazing Hubble images are made. It's the exact same as what I talked about (plus the image aligning since you have to combine images) but in a much flashier format.
I did my best to provide some pictures to illustrate what I was talking about, but they weren't anything exciting. What would be really exciting is if you could see this for something really cool. Like a Hubble image.
Turns out, you can! PBS put together a wonderful little flash on how the amazing Hubble images are made. It's the exact same as what I talked about (plus the image aligning since you have to combine images) but in a much flashier format.
Jesus Camp
I know I’m behind the curve here, but now that I’ve graduated, I’ve got a lot more free time to read books, watch movies, play games, talk to friends and all that jazz.
One of the things that I’ve only just now gotten around to is watching Jesus Camp. I knew it was scary just how crazy these people were, so for the most part, it wasn’t surprising, but I figured I’d share my thoughts on it anyway.
In the very first scene, we see the leader of the camp, Becky Fisher, screaming at kids about how, if God can do anything, then he should be able to fix “this sick ‘ole world”. Hahahaha. Sure. Just pray. Yeah…. Shame prayer doesn’t work. This is again demonstrated later when Rachael (another girl in the camp) prays to get a strike while bowling. She rolls a gutter ball.
She then tells kids that, “We have too many Christian grown ups who are fat and lazy.” Sure. And she’s one of them. She’s by far the fattest one in the entire film and is later seen teasing her hair. Yeah. That’s getting something done… Shame she can’t get these kids to do something productive instead of harassing people with nonsense.
Next, she leads the group in prayer in tongues. Now, back in high school, I did a bunch of theater. One of the things that we had to learn was how to quickly speak gibberish and make it convincing enough to actually sound like a language. It’s not that difficult, but it takes some practice. When you’re good at it, it rolls right off your tongue and sounds pretty good to someone who doesn’t know you’re not actually speaking gibberish. The thing that amazed me about this is that these people aren’t even good at it! Their gibberish is running through a few mushed up syllables. And they really thing it means something! The adults were obviously better than the kids, but having a lifetime of practice, they’d better be.
The film then shows the camp leader watching the video of these kids and saying, “she’s not out of it. She’s very aware of what’s going on.” Well yeah. You know what’s going on, but that doesn’t mean it has to make sense or have some profound meaning. And it certainly doesn’t mean that they’re “hooking up with the Spirit.”
Becky brags about being able to go onto a playground and tell kids about God and get them to see “visions”. Well duh. Kids are imaginative and open to suggestion. Why do you think that psychologists are required to undergo training before they ask kids about experiences? They have to make sure they don’t lead the kids inadvertently. There’s numerous cases out there (many times involving ignorant church officials) in which people asking them questions have led kids to believe that they were sexually abused, leading to emotional trauma when in fact, no such thing had occurred. What Becky does is probably less harmful, but is no more meaningful than this. The fact that she brags about it is just disgusting.
She talks about suicide bomber camps training kids and says that it’s great that they can get kids so dedicated. She says, “I want to see young people who are as dedicated to the cause of Jesus Christ as the young people are to the cause of Islam. I want to see them radically laying down their lives for the Gospel…”
Wow.
Next up we see one of the kids, Levi, watching a Creationist propaganda video. It’s got the normal lies about what science actually says (“Did we come from an explosion? Are you a gob of goo?”). The mother then starts talking about Global Warming, teaching her son to dismiss it because it’s “only gone up 0.6ยบ.” Talk about a lack of understanding of the issue. Levi then says he, “feels Galileo made the right choice by giving up science for faith.”
E pur si muove anyone?
The mother says the country was founded on Judeo-Christian values. Treaty of Tripoli Article 11 pwns u biotch!
Another family does the Pledge of Allegiance. Except it’s not even the one to the US. And these people claim that we’re the ones trying to subvert the pledge? LOL!
At the camp, Becky stars off with a brain numbing sermon about how sin is like a baby tiger, that if you feed it, it gets big and eats you. Then right in the middle of it, she goes on a crazy rant about how evil Harry Potter is, how he’s an “enemy of God”, and how if he was in the OT, he’d be “put to death.” What a sweet message.
She then does the magic trick of the guilt trip, trying to make people feel bad for being humans because they’re not Christian enough. And you “can’t have phonies in the army of God.” “You know what need to repent of.” Sounds more like an interrogation technique than anything else. Especially when some of the kids antagonize another for looking like Harry Potter and another for having seen it at his father’s house.
One of the male leaders of the camp gets testy about ghost stories because they, “don’t honor God.”
Rachael has a segment about “dead churches” in which she says that God likes churches in where people are jumping up and down and being overly excited. Funny. If I was invited to a party in my honor, I’d prefer people not act like complete idiots. At least not till I’ve had a few drinks too…
In another scene, Levi is practicing a sermon he’s going to be giving about how he feels that his generation is a key generation for blah blah blah blah…. He then says that he’s not the one that writes it, but that it’s God writing it. Hmmm… no. I think it’s the pastors that said the exact same thing earlier that you’re cribbing from. I guess citing your sources is optional for these guys.
Later on, there’s more trivial examples of doing nothing while thinking they’re doing something by smashing cups with hammers. There’s a lot of crying about it too.
The trip to Haggert’s New Life Church is especially ironic given his recent stumble.
In the end, Becky gets on a radio show and outright admits that she is quite happy to indoctrinate children and that democracy is bad. She’s just scary. And giving her access to children is worse.
One of the things that I’ve only just now gotten around to is watching Jesus Camp. I knew it was scary just how crazy these people were, so for the most part, it wasn’t surprising, but I figured I’d share my thoughts on it anyway.
In the very first scene, we see the leader of the camp, Becky Fisher, screaming at kids about how, if God can do anything, then he should be able to fix “this sick ‘ole world”. Hahahaha. Sure. Just pray. Yeah…. Shame prayer doesn’t work. This is again demonstrated later when Rachael (another girl in the camp) prays to get a strike while bowling. She rolls a gutter ball.
She then tells kids that, “We have too many Christian grown ups who are fat and lazy.” Sure. And she’s one of them. She’s by far the fattest one in the entire film and is later seen teasing her hair. Yeah. That’s getting something done… Shame she can’t get these kids to do something productive instead of harassing people with nonsense.
Next, she leads the group in prayer in tongues. Now, back in high school, I did a bunch of theater. One of the things that we had to learn was how to quickly speak gibberish and make it convincing enough to actually sound like a language. It’s not that difficult, but it takes some practice. When you’re good at it, it rolls right off your tongue and sounds pretty good to someone who doesn’t know you’re not actually speaking gibberish. The thing that amazed me about this is that these people aren’t even good at it! Their gibberish is running through a few mushed up syllables. And they really thing it means something! The adults were obviously better than the kids, but having a lifetime of practice, they’d better be.
The film then shows the camp leader watching the video of these kids and saying, “she’s not out of it. She’s very aware of what’s going on.” Well yeah. You know what’s going on, but that doesn’t mean it has to make sense or have some profound meaning. And it certainly doesn’t mean that they’re “hooking up with the Spirit.”
Becky brags about being able to go onto a playground and tell kids about God and get them to see “visions”. Well duh. Kids are imaginative and open to suggestion. Why do you think that psychologists are required to undergo training before they ask kids about experiences? They have to make sure they don’t lead the kids inadvertently. There’s numerous cases out there (many times involving ignorant church officials) in which people asking them questions have led kids to believe that they were sexually abused, leading to emotional trauma when in fact, no such thing had occurred. What Becky does is probably less harmful, but is no more meaningful than this. The fact that she brags about it is just disgusting.
She talks about suicide bomber camps training kids and says that it’s great that they can get kids so dedicated. She says, “I want to see young people who are as dedicated to the cause of Jesus Christ as the young people are to the cause of Islam. I want to see them radically laying down their lives for the Gospel…”
Wow.
Next up we see one of the kids, Levi, watching a Creationist propaganda video. It’s got the normal lies about what science actually says (“Did we come from an explosion? Are you a gob of goo?”). The mother then starts talking about Global Warming, teaching her son to dismiss it because it’s “only gone up 0.6ยบ.” Talk about a lack of understanding of the issue. Levi then says he, “feels Galileo made the right choice by giving up science for faith.”
E pur si muove anyone?
The mother says the country was founded on Judeo-Christian values. Treaty of Tripoli Article 11 pwns u biotch!
Another family does the Pledge of Allegiance. Except it’s not even the one to the US. And these people claim that we’re the ones trying to subvert the pledge? LOL!
At the camp, Becky stars off with a brain numbing sermon about how sin is like a baby tiger, that if you feed it, it gets big and eats you. Then right in the middle of it, she goes on a crazy rant about how evil Harry Potter is, how he’s an “enemy of God”, and how if he was in the OT, he’d be “put to death.” What a sweet message.
She then does the magic trick of the guilt trip, trying to make people feel bad for being humans because they’re not Christian enough. And you “can’t have phonies in the army of God.” “You know what need to repent of.” Sounds more like an interrogation technique than anything else. Especially when some of the kids antagonize another for looking like Harry Potter and another for having seen it at his father’s house.
One of the male leaders of the camp gets testy about ghost stories because they, “don’t honor God.”
Rachael has a segment about “dead churches” in which she says that God likes churches in where people are jumping up and down and being overly excited. Funny. If I was invited to a party in my honor, I’d prefer people not act like complete idiots. At least not till I’ve had a few drinks too…
In another scene, Levi is practicing a sermon he’s going to be giving about how he feels that his generation is a key generation for blah blah blah blah…. He then says that he’s not the one that writes it, but that it’s God writing it. Hmmm… no. I think it’s the pastors that said the exact same thing earlier that you’re cribbing from. I guess citing your sources is optional for these guys.
Later on, there’s more trivial examples of doing nothing while thinking they’re doing something by smashing cups with hammers. There’s a lot of crying about it too.
The trip to Haggert’s New Life Church is especially ironic given his recent stumble.
In the end, Becky gets on a radio show and outright admits that she is quite happy to indoctrinate children and that democracy is bad. She’s just scary. And giving her access to children is worse.
Sunday, July 06, 2008
Creationists will love this one
Man, doesn't this sound too good to be true for creationists:IT'S an embarrassing gap in astronomers' knowledge. Despite relying on type Ia supernovae as tools to measure the dark energy speeding up the universe's expansion, they still don't know exactly what causes the blasts. Now the picture has got even fuzzier."Bwa ha ha ha! Those crazy scientists don't know what's going on! They're all confused because of 'gaps'! Bwa ha ha ha!"
Ugh. This is why I can't stand most science journalism. It takes what's a pretty cool journal article about people figuring out how our universe works and refining our knowledge, and acts like they're a bunch of bumbling morons.
*headdesk*
If you didn't follow the link to read the rest of the article, it basically says that a new paper is challenging the long held idea that type Ia supernovae come from white dwarfs pushed over their Chandrasekhar limit (the mass limit for a core before it explodes as a supernova) by mass being dumped on them from a companion star.
The evidence thus far seems to fit pretty well. There's not much hydrogen in the spectra, so we know these supernovae aren't normal stars, still surrounded by their hydrogen atmosphere. The total amount of energy fits well. The shape of the light curve works. We see them in old galaxies which should have lots of white dwarfs.
But the issue now is that recent studies have been indicating that we're seeing them in places with lots of active star formation too. In fact, it's being suggested there's even a correlation between the number of Ia supernovae and the amount of star formation. If that's the case, then this suggests that, at the very least, old dead cores can't be the only way to form Ia supernova.
So what's the "new" explanation? The paper doesn't say. There's a hint at the end effectively saying "stay tuned for paper #2!" but no word on what it's going to say yet.
But what does this all have to do with the part of the article I quoted earlier about the age of the universe?
Absolutely nothing!
Regardless of whether or not we know exactly what's causing these supernovae, we still know they're excellent standard candles because we can check them against other distance measuring methods (such as the P-L relation of Cepheids or the Tully-Fisher relation). It doesn't matter if it's an overburdened white dwarf or God letting off cosmic farts. Either way, we've observed that they all have an absolute magnitude of -19.3.
Not knowing exactly what causes type Ia supernovae doesn't change the fact that we know how bright they are! Since that doesn't change it doesn't make any difference on our understanding of the age and size of the universe! Tossing in that gibberish about the size and age of the universe is a complete non-sequitor.
Pritchet, C., Howell, D., & Sullivan, M. (2008). The Progenitors of Type Ia Supernovae The Astrophysical Journal, 683 (1) DOI: 10.1086/591314
Thursday, June 26, 2008
Frack
Two years ago, I first got into the show Battlestar Galactica. Since then, I've been a gigantic fan (who knew I'd get into a show created by Mormons). The episode a few weeks back was, well, a cliffhanger to put it mildly. Unlike most episodes, it didn't end with the typical "stay tuned for a sneak peek at next week's episode" and hinted that BSG wouldn't be on for a bit.
How long is a bit?
The rest of the fracking year.
Frack.
Oh well. I suppose that will give the rest of you a chance to catch up.
For those that don't understand the term "frack", it's the term that characters use in the show as a substitution for the obvious swear word. And yes, it has worked it's way into my everyday language.
How long is a bit?
The rest of the fracking year.
Frack.
Oh well. I suppose that will give the rest of you a chance to catch up.
For those that don't understand the term "frack", it's the term that characters use in the show as a substitution for the obvious swear word. And yes, it has worked it's way into my everyday language.
Monday, June 23, 2008
George Carlin: 1937 - 2008
I just heard that George Carlin has died of heart failure. Here's one of my favorite segments of his as a bit of tribute.
Thursday, June 19, 2008
Monday, June 16, 2008
Thursday, June 12, 2008
Spiral structure
I’m not entirely sure why, but recently, in various forums I hang out on, I’ve been seeing a particular creationist argument pop up that’s fairly annoying. The argument is that the universe can’t be as old as astronomers say it is because, if it were, the spiral arms in galaxies would “wind up”.
This argument is pretty convincing at first, because it plays on the expectation that galaxies are fairly straightforward systems without dirty little tricks up their sleeves. If this were the case, galaxies would behave like the solar system wherein the things towards the center go around quickly and objects towards the edges slowly work their way around. Thus, if you started everything on a straight line, the inner part would have orbited several times while the outer edges would barely have budged thanks to the fact that those inner bits not only move faster, but have a shorter distance to travel in their smaller orbits.
Expectation wise, galaxies shouldn’t have graceful arms that tend to only go about half a full turn. Unless, of course, those expectations are wrong. And I’m sure by now most readers are anticipating what should be the obvious answer: They are.
The first thing that’s wrong is that galaxies don’t behave like our solar system. This was first realized in 1959 in the galaxy M33 by Louise Volders. In the 1970’s, this non-Keplarian motion was discovered in more and more galaxies by Vera Rubin, which is one of the foundations for the need for Dark Matter. Instead of velocities trailing off in an exponential decay like we see in the solar system, most galaxies tend to have fairly flat velocity curves as shown in the figure. A flat rotation curve means that galaxies don’t wind up and if they do, it would be very slowly.
Of course, this raises an even more interesting question. Even though we’ve established that these arms could be very old, it still doesn’t say anything about why you have regions in the galaxy where they exist in the first place. What’s so special about spiral structure!?
The answer to this question is profound because it gets to the very nature of what spiral arms are and, as with before, it’s something that completely defies what you’re probably thinking if you’re not already familiar with this topic: Spiral structure is the result of spiral density waves...
Whatever the hell that means.
Unfortunately, there’s no real good way I’ve yet come across to explain this. Silly analogies with traffic jams tell you what is going on, but says nothing of why it happens. And that “why” is fairly important, lest we be accused of making up just-so stories.
I’m going to skip the math since it requires a course in mechanics and quite a bit of calculus to go through and I’ll just get to the heart of what it reveals.
Let’s start off with an idealized galaxy in which we have everything as simple as we can get it. Let’s pretend the galaxy is a perfectly uniform distribution of gas and dust in perfectly circular orbits around the center. Yeah right. No galaxy really starts off that way. Galaxies are in clusters and being acted on by one another. Many galaxies have satellites that perturb them and they were formed from smaller lumps that have gotten cannibalized. They’re dynamic places, so if we introduce some perturbations to the system, we can ask what happens then.
No need to really do this for the whole galaxy at this point. We can just look at the case of what would happen to any single star. It ends up that if you knocked a star out of its ideal orbit, the combined forces of the rest of the galaxy would work to try to restore its ideal position. But as with most restorative forces, it will tend to overshoot. Thus, you get harmonic motion. Not only do you get this towards and away from the center of the galaxy though, you also get it in the direction of motion. The combination of these two motions means that the star would make little orbits about its idealized location. The Sun does this too. Its motion in relation to the idealized point it should be (known as the Local Standard of Rest or LSR) is known as “Peculiar Motion”.
So let’s try to picture what that looks like. In this image, I’ve drawn the idealized LSR for our star in green. On top of that, I’ve sketched the path it would travel around an idealized point in red at four different points in the full orbit. The extent of this is grossly exaggerated of course, but it will illustrate the point.
Now let’s have the star make an integer number of rotations around its small circle every time it goes around the full big circle. If we take the star to be at its furthest from the center of the galaxy at point a, then it would be at its closest at b, furthest again at c, and closest again at d. Now putting the overall true motion of the star (in blue) in with the smaller wobbles, the true motion becomes apparent: Stars have elliptical orbits.
What’s more, the way these elliptical orbits line up isn’t the same at all distances from the center of the galaxy. Rather, the orientation of the major axis of the ellipse will rotate as you move out. That means that if we drew is successive ovals, each one would be slightly skewed resulting in a pattern like the one I’ve shown here.
The result of these skewed orbits is that at some points around the galaxy, stars tend to all bunch up more than at other places. And what happens when you get a bunch of massive things bunching up? It creates a gravitational potential. The result is that stars will speed up as they fall in making a lack of stars on the trailing edge but then be slowed down again as they exit, creating a pile up on the front edge. If spiral arms really were some magical place that could get wound up, we shouldn’t expect to see this. But we do, which suggests that the Creationist version of spiral arms doesn’t fit reality.
And this is what a spiral arm is. It’s the crowding together of a bunch of stuff as its slowed down exiting the potential well caused by the spiral wave. And it turns out these things are very stable. So the Creationist claim that they must be very young because galaxies should “wind up” is just wrong. It’s using a horribly outdated idea of what spiral structure is. Not that this is surprising.
But how robust is this explanation? Turns out it does very well to explain not just the very nice two armed spirals like M51, but it also can explain the not so neat spiral galaxies like M101. It just takes a different number of orbits around the small path per full orbit. And even the flocculent spirals with patchy arms can be explained through this, using non-integer numbers of rotations or linear combinations of many states.
I hope that clears up what’s really going on with spiral structure. If you’re really interested in seeing the math behind this, it should be in most junior/senior level astronomy texts.
This argument is pretty convincing at first, because it plays on the expectation that galaxies are fairly straightforward systems without dirty little tricks up their sleeves. If this were the case, galaxies would behave like the solar system wherein the things towards the center go around quickly and objects towards the edges slowly work their way around. Thus, if you started everything on a straight line, the inner part would have orbited several times while the outer edges would barely have budged thanks to the fact that those inner bits not only move faster, but have a shorter distance to travel in their smaller orbits.
Expectation wise, galaxies shouldn’t have graceful arms that tend to only go about half a full turn. Unless, of course, those expectations are wrong. And I’m sure by now most readers are anticipating what should be the obvious answer: They are.
The first thing that’s wrong is that galaxies don’t behave like our solar system. This was first realized in 1959 in the galaxy M33 by Louise Volders. In the 1970’s, this non-Keplarian motion was discovered in more and more galaxies by Vera Rubin, which is one of the foundations for the need for Dark Matter. Instead of velocities trailing off in an exponential decay like we see in the solar system, most galaxies tend to have fairly flat velocity curves as shown in the figure. A flat rotation curve means that galaxies don’t wind up and if they do, it would be very slowly.Of course, this raises an even more interesting question. Even though we’ve established that these arms could be very old, it still doesn’t say anything about why you have regions in the galaxy where they exist in the first place. What’s so special about spiral structure!?
The answer to this question is profound because it gets to the very nature of what spiral arms are and, as with before, it’s something that completely defies what you’re probably thinking if you’re not already familiar with this topic: Spiral structure is the result of spiral density waves...
Whatever the hell that means.
Unfortunately, there’s no real good way I’ve yet come across to explain this. Silly analogies with traffic jams tell you what is going on, but says nothing of why it happens. And that “why” is fairly important, lest we be accused of making up just-so stories.
I’m going to skip the math since it requires a course in mechanics and quite a bit of calculus to go through and I’ll just get to the heart of what it reveals.
Let’s start off with an idealized galaxy in which we have everything as simple as we can get it. Let’s pretend the galaxy is a perfectly uniform distribution of gas and dust in perfectly circular orbits around the center. Yeah right. No galaxy really starts off that way. Galaxies are in clusters and being acted on by one another. Many galaxies have satellites that perturb them and they were formed from smaller lumps that have gotten cannibalized. They’re dynamic places, so if we introduce some perturbations to the system, we can ask what happens then.
No need to really do this for the whole galaxy at this point. We can just look at the case of what would happen to any single star. It ends up that if you knocked a star out of its ideal orbit, the combined forces of the rest of the galaxy would work to try to restore its ideal position. But as with most restorative forces, it will tend to overshoot. Thus, you get harmonic motion. Not only do you get this towards and away from the center of the galaxy though, you also get it in the direction of motion. The combination of these two motions means that the star would make little orbits about its idealized location. The Sun does this too. Its motion in relation to the idealized point it should be (known as the Local Standard of Rest or LSR) is known as “Peculiar Motion”.So let’s try to picture what that looks like. In this image, I’ve drawn the idealized LSR for our star in green. On top of that, I’ve sketched the path it would travel around an idealized point in red at four different points in the full orbit. The extent of this is grossly exaggerated of course, but it will illustrate the point.
Now let’s have the star make an integer number of rotations around its small circle every time it goes around the full big circle. If we take the star to be at its furthest from the center of the galaxy at point a, then it would be at its closest at b, furthest again at c, and closest again at d. Now putting the overall true motion of the star (in blue) in with the smaller wobbles, the true motion becomes apparent: Stars have elliptical orbits.What’s more, the way these elliptical orbits line up isn’t the same at all distances from the center of the galaxy. Rather, the orientation of the major axis of the ellipse will rotate as you move out. That means that if we drew is successive ovals, each one would be slightly skewed resulting in a pattern like the one I’ve shown here.The result of these skewed orbits is that at some points around the galaxy, stars tend to all bunch up more than at other places. And what happens when you get a bunch of massive things bunching up? It creates a gravitational potential. The result is that stars will speed up as they fall in making a lack of stars on the trailing edge but then be slowed down again as they exit, creating a pile up on the front edge. If spiral arms really were some magical place that could get wound up, we shouldn’t expect to see this. But we do, which suggests that the Creationist version of spiral arms doesn’t fit reality.
And this is what a spiral arm is. It’s the crowding together of a bunch of stuff as its slowed down exiting the potential well caused by the spiral wave. And it turns out these things are very stable. So the Creationist claim that they must be very young because galaxies should “wind up” is just wrong. It’s using a horribly outdated idea of what spiral structure is. Not that this is surprising.
But how robust is this explanation? Turns out it does very well to explain not just the very nice two armed spirals like M51, but it also can explain the not so neat spiral galaxies like M101. It just takes a different number of orbits around the small path per full orbit. And even the flocculent spirals with patchy arms can be explained through this, using non-integer numbers of rotations or linear combinations of many states.
I hope that clears up what’s really going on with spiral structure. If you’re really interested in seeing the math behind this, it should be in most junior/senior level astronomy texts.
Sunday, June 08, 2008
Creation Science 101: Plants are not alive
What is death? Death is when something with life dies. Does that mean plant death? No. God tells us in Leviticus and many other places that life is in the blood of the creature. "For as for the life of all flesh, its blood is identified with its life."And we're supposed to take Creationists seriously?
So, death is when someone or something with blood in it dies.
~Jeannie Fulbright
And you've got to appreciate how amazingly inept these people are at logic. Take out the nonsensical qualification in the last sentence and you get, "death is when someone or something ... dies."
What an amazingly profound and useful definition. Really, does that qualify as circular reasoning? It doesn't even go in a circle. It just sits in one spot. This is supposed to be "upper-level science with the most in-depth, insightful science curriculum"?
I don't think I'll be buying any of her textbooks.
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