Thursday, July 30, 2009

Happy National Cheesecake Day!

I don't know why we need a National Cheesecake Day, but mmmm do I love me some cheesecake.

If you live near a Cheesecake Factory, their slices are 1/2 price today. If not, here's the recipe for the best cheesecake I've ever had:

Ingredients
- 1 box Famous Amos cookies
- 2 sticks of butter
- 2 1/2 pounds (5 packages) cream cheese, softened
- 1 3/4 cups sugar
- 2 tbsp flour
- 1/4 tsp salt
- 2 egg yolks
- 5 whole eggs
- 1 tsp vanilla extract
- 1 cup sour cream
- 12 squares Baker's white baking chocolate (2 packages)

Instructions
1. Open bag of cookies slightly and press out air. Crush cookies into a fine powder using a rolling pin, wine bottle, or by hand if nothing else is handy.
2. Melt 1 1/2 sticks butter in microwave and combine with cookie crumbs in bowl. Mix well.
3. Press half of the buttered cookie crumbs into the bottom of a springform pan.
4. Soften cream cheese in microwave on LOW for a few minutes, being careful not to burn.
5. Beat well and add (one at a time): sugar, flour, salt, eggs, vanilla, sour cream, and chocolate.
6. Use remaining butter to butter the sides of the springform pan to keep it from sticking. Then pour 1/2 batter into springform pan on top of crust.
7. Bake in oven at 200┬║ F for ~3 hours or until cake is reasonably firm to the touch (it should still jiggle as it is removed from oven). Butter from crust will drip, so make sure to have a second pan or cookie sheet underneath to catch the drippings.
8. Turn off oven but leave cake in for up to an hour to allow it to cool. This will prevent cracking.
9. Refridgerate overnight.

Notes
Makes 2 cheesecakes. Additionally, while mixing initially, be very cautious of using a hand mixer. Unless your cream cheese is very warm it will be very thick and can potentially burn out hand mixers.

Wednesday, July 29, 2009

Playing around with the Layout

Think I've just about got everything how I wanted it.

I finally updated blogger to the XML stylesheet so I could more easily add a few things I've been wanting.

The major changes are that I've added a sidebar widget to keep track of all those tags I've been tagging. I also updated the way the archive is displayed since it was starting to get pretty long listing every month. I also just got talked into using Twitter, so there's also a new sidebar for that, although I've buried it at the bottom since it's relatively uninteresting.

A minor change is that a few of my links have disappeared. The widget that controls links doesn't let me make subgroups for whatever reason. Perhaps I'll just add a few more links sections. The only one I feel was particularly important was the one to me Book Reviews/Reading List.

If anything is wonky for anyone, let me know and I'll do some more poking.

Who thought this was a good idea....

Twilight is going to be made into a MMO.

....

Whut?

I haven't really followed much of Twilight, but I did watch the movie and thought it was laughably stupid. I think it was best summed up here by saying:
The Twilight series ... works almost exclusively as a campaign for abstinence and the evilness of male hormones. The story treats sexuality as a disease, as a vampire. A boy who is trouble because he can’t hold back his urges for a girl.
Yep. That'll work well as a foundation for a video game....

I still think Abbie puts Twilight into better perspective than anyone else.

Haumea and Friends

Blogging on Peer-Reviewed ResearchThe past few years, much public attention has been brought to the outskirts of our solar system by the demotion of Pluto. Love it or hate it, suddenly the Kuiper Belt is getting a lot more attention than it used to. Sometimes, people even know the names of some of the objects in it. But that's only the bigguns like Quaoar and Sedna. There's many others out there, and one that gets little attention is Haumea.

Haumea is only 1/3 the mass of Pluto, but is notable because of its unusual shape: It's elongated. Additionally, it has a very fast rotation period (only 4 hours). Lastly, it has 2 moons and at least 6 other, smaller objects associated with it due to to similar surface properties and orbits. As such, the leading theory is that Haumea was struck by a large object which shattered it, causing it to be misshapen and knocking bits off.

But a recent paper disagrees. It notes that the velocity dispersion for the other objects associated with the main body (not the moons) is too low for what we would expect to see in a collision.

Instead, it proposes a new hypothesis: A collision long ago may have given Haumea its unusual shape and fast spin, but the ejected material coalesced into a loosely bound moon which slowly drifts away. That moon then undergoes another collision which created the collisional family.

Although it sounds like it fits this particular piece of evidence better than the single collisional model, I'm still not completely convinced. The reason is that, in today's Kuiper Belt, the time scale for collision is somewhere on the order of 1012 years. Even if you want to rewind this and say it all happened earlier in the history of the solar system when chances could be 100 times more likely, that still leaves the chance for the initial collision at 1010 years. (The authors use another estimation here and somehow come up with a timescale of ~8 x 106 years here.) To invoke a second collision would be even more unlikely since the new target (the satellite) would be a much smaller target than Haumea before the initial impact. Even using the author's calculation of 8 x 106 years for the initial collision, multiplying that by a second collision puts the timescale over 1013 years! Keep in mind the age of the solar system is just 4.5 x 109 years.

So while the hypothesis may seem to favor a double collision, the math says it's not likely.

Schlichting, H., & Sari, R. (2009). THE CREATION OF HAUMEA'S COLLISIONAL FAMILY The Astrophysical Journal, 700 (2), 1242-1246 DOI: 10.1088/0004-637X/700/2/1242

Tuesday, July 28, 2009

Shakin' Red Giants in NGC 6397

Blogging on Peer-Reviewed ResearchA way long time ago, I introduced the concept of asteroseismology. It's a pretty interesting concept that uses the vibrational modes of stars like we do seismology on Earth to probe the interior of stars. When I first wrote on it, a friend from MSU was still working on it, so I heard a lot about it, and intended to write more on it (I even created a tag for it). But I never really did.

One of the things about this technique is that it requires you to have a good handle on how the star you're observing is vibrating. Any any potential star for this has to be vibrating in the right way. Variations like the ones from Cepheids can't give us the information we need. Delta Scuti stars are a class of variables that fits the bill, but finding more classes always helps to increase our knowledge. (In theory most stars will have the right kind of vibrations, but will generally just be too small to notice from any distance.)

A new paper suggests that we may have discovered a new class: Metal poor red giants.

In observing several of these stars, they found at least one that seems to be jiggling just right for the oscillations necessary (called "solar-like" for historical reasons). Several others seemed to be exhibiting the same sort of pulsations, but due to shoddy data with low signal-to-noise ratios as well as some overexposing, they couldn't be sure.

As such, the authors are calling this discovery "tenuous". Still, it's an interesting starting point for further investigation.

Stello, D., & Gilliland, R. (2009). SOLAR-LIKE OSCILLATIONS IN A METAL-POOR GLOBULAR CLUSTER WITH THE

The Astrophysical Journal, 700 (2), 949-955 DOI: 10.1088/0004-637X/700/2/949

Willful Ignorance

In my post the other day about Ray, I pointed out that he admitted to not caring one iota about the facts. If it wasn't in the Bible, it doesn't exist. Such thinking is nothing more than willful ignorance.

Here's another example. UC Berkley put a sculpture of some DNA outside their science building. Parents of children at an Elementary school that can see the sculpture are complaining about it. Why?
“My daughter suggested that it was funny,” said John Copeland, whose 7-year-old daughter attends summer camp there. “She shouldn’t be talking to me about this. Now I’m forced to explain genetics to her, and why the Bible doesn’t say anything about it.”
Last I checked, the Bible didn't talk about airplanes, penicillin, computers, or numerous other things. Does Mr. Copeland intend to keep her away from these things as well?

Another commenter said:
If this piece weren’t visible to passersby and available for children to play on, I would not have a problem with it.
Wut?

A sculpture of DNA is so offensive that you want it hidden from public sight? Why would they want such a thing?!
It’s vile and offensive, and kids have no business seeing what God thought fit to hide from our eyes.
I guess this guy condemns all astronomy too, on the basis that most of the universe is hidden from our view without special instrumentation, just like DNA is.

This willful ignorance is stupid and these people should not be given any sort of public platform. As Thunderf00t pointed out, these people serve only to retard our knowledge and are a detriment to society.

EDIT: As pointed out, this story looks to be a parody. Damn those parody stories that are no more ridiculous than things these people actually say!

Sunday, July 26, 2009

Ray Comfort vs. Thunderf00t

Ooh! It's finally here! Awhile ago, the youtube user Thunderf00t (most well known for his Why do people laugh at creationists? series and smackdowns of VenomfangX), who I'll call TF for the sake of brevity, took up Ray Comfort's (the banana is proof of God and Peanut Butter disproves evolution guy) challenge to a debate. After Ray initially balked and wanted $10,000 for it, he eventually gave in. And now the discussion is online.

*Gets out the a bottle of liquor and prepares for the stupid fest*

Right off the bat, Ray shoves his foot in his mouth:
Why the name Thunderf00t? I mean, is it African-American?
WTF? Does he mean “Native American”?

When TF says it came from his online capture-the-flag games which he used Thunderf00t as his character name, Ray immediately poisons the well saying
I thought it was because you liked stomping on Christians
Yep. Rational discussion right there.

Only 51 seconds in and there's 9 10 minute videos like this?

*Takes a shot*

At 2:12 in, Ray starts making his unsubstantiated claims:
I know [what happened in the beginning]. You don't know. I know what was in the beginning. “In the beginning God created the heavens and the earth.” You don't know. I do.
By 7:03, Ray's chastising TF for our generation thinking they're right. As if that doesn't apply to his claims as well.

9:42 comes along and Ray makes it pretty clear that he's not listening and is just hammering his talking points. He keeps beating on about how this universe is a creation, even after TF has pointed out that that's an assumption that Ray has not supported. But Ray just keeps pounding it with his strawman of “nothing” creating something. Yet TF has never once made this claim.

10:16: Ray claims that TF's position is “all these things [that] happened by sheer accident, that they just formed by themselves...”

As if that's not bad enough, Ray's claiming it's “intellectually dishonest” to admit “we just don't know.” Since when is admitting the limits of knowledge “intellectually dishonest”?!

PART 2

1:00 Ray's claiming DNA is “language” and using the writing in the sand analogy. TF points out that another form of the argument Ray's using is “paintings have painters....”. TF points out that there's a reason Ray can claim this (which Ray calls “common sense”). TF points out that he can make this claim because we've seen people paint paintings. Ray counters that he'd never need to see someone actually paint to know paintings were painted because he'd know it just wouldn't “happen by itself.” (Sounds like what I said watching another video with Ray.)

TF asks if “rainbows just happened by themselves.”

Ray's response is priceless: “No. God created them. *smug smile* I know. Says it in scripture.” Ray also claims that God creates the rain as well.

When confronted with a completely naturalistic explanation for rain, Ray then cops out, effectively saying, “Well God still did it.” Even snow: Goddidit.

By 4:05, TF finally gets to the point that Ray is beating around: “So you're asking, can I violate the Law of Conservation of Energy?”

Ray says of course he can't: “You can't make anything from nothing.” Back to beating on his assumption of “nothing.”

Ray then attempts to say that, no matter what, TF can't know there's no evidence for God because you'd have to know everything to know that, of course failing to realize that since he doesn't have omniscience either, this applies to his claim of knowledge as well. But that's ok. Because the Bible tells him everything.

Finally, at 6:40, Ray is finally able to get to his next talking point after spending several minutes trying to change the topic before TF can make a full answer (Gish Gallop much?). His next claim: Man is different than animal because we are a “moral” creature.

TF's response is to point out that many of our morals are dependent on just how society will permit it and whether or not a behavior will cause the extinction of the civilization. Simple explanation, no need for additional causes.

PART 3

0:43 – Ray quickly changes the subject again without bothering to address TF's points. Next subject: Where do people go when they die.

Again, TF calls Ray on the assumption that they “go” anywhere. Ray dances around invoking the “soul” and then equivocates it with “life” with absolutely no basis for doing so.

At 2:40 Ray invokes an argumentum ad populum saying that since most people believe in afterlives, that should be the default state of assumption.

4:30, Ray's claiming that his interpretation of the scriptures must be right because “it's clear to [him].”

At 5:38, Ray makes a really weird claim.
I know God in the same way I know my wife. It's an intimate relation, relationship with her.
Woah there buddy. Don't need to know what goes on behind closed doors.

PART 4

Most of this section is TF talking about how, from a psychological standpoint, people are tuned to follow an “alpha figure” and when they do, it gives them happiness and comfort via a placebo effect. This was in response to Ray's claiming that, because he woke up one night and acceptance of God suddenly dawned on him and made him feel good, that God must be real.

PART 5

Ray leads this part off asking if TF is using this to imply that people are easily deceived. TF replies that he does, and Ray would have to agree with this by saying everyone not following his religion are being deceived by other religions.

TF admits that even he can be easily deceived as well, but reiterates his point that people will believe and act in ways that don't necessarily follow logic (such as the Milgram experiment) when given authority figure.

At 8:18 TF asks a question that surprised me, because it's answer should have been so expected coming from Ray. TF asks “What other definition is there for “morality” [besides what benefits and creates a stable society]?”

Ray instantly claims that TF has no absolute morality (although in part 4, TF stated clear as day that he did because there are absolute limits on actions that will not create the extinction of a society, thus making it obvious again, that Ray isn't listening and just hammering his points) and that he does have another, better definition: The 10 Commandments.

PART 6

Ray's first question in this section is if TF had to choose whether to save his “rotten neighbor” or his dog from drowning, who would he save? TF answers that he would save the dog because he doesn't feel any empathy for someone who's his enemy.

I think a better answer would be “define 'rotten'.”

Next topic: abortion.

Ray immediately tries to get TF to admit that “life” starts at conception. TF tries to remind him that it's not self viable.

TF then asks, whether or not a zygote that develops into a fetus without a head, it would still have the soul that's so important to Ray. Ray gives an honestly incredulous, “I don't know. I have no idea.” But before even considering the question, he goes, “But it's dead.” His reasoning? “If it hasn't got a head, it's dead.”

TF tries to explain it, but Ray quickly ducks away hiding behind the Bible saying “the Bible speaks of a woman being 'with child' again and again. It doesn't say with fetus or with cells.” Thus, anything (unless without a head) is a child because the Bible doesn't contain any mention of anything else (not that they'd have known about it 2000 years ago).

TF goes back to the point that there's no distinguishable difference between the good feelings one gets following a “phantasmal” authority figure as Ray does following his God. TF asks how Ray can distinguish between the two since the results are apparently identical. Instead of answering, Ray goes on a rant about idolatry and drags Dawins' understanding of God into it. Not letting him get away with it, TF drags Ray back to it and Ray responds with the usual, “Bible says so.”

At that point, they start discussing how to conclude which leads us to

PART 7

They go back to the topic at the end of the last one on distinguishing “mental teddy bears” vs God. Ray's only answer is that it's in the Bible, so God is real so he's following that to get eternal life.

TF asks if eternal life would really be a blessing or a curse. Ray immediately answers it would be the greatest of blessings because “We live in a fallen creation. Everything is futile. We're about to die, every one of us. Look in the mirror, things are degenerating. The future is bleak...”

TF interrupts and says that the future is bright because of the accumulation of knowledge. This is an interesting split between the two which shows where their focus lies. To Ray, he's only good because God says so and he wants eternal life for himself. He doesn't seem to genuinely care about others, but only does so because God tells him to, so he fakes it. TF meanwhile, actually cares about the improvement of the species. The question of what's in it for him after he dies doesn't even seem to cross his mind.

Again, it's clear who has more mettle.

TF then points out that the retarding of knowledge Ray does by sowing disinformation about evolution is what gets him so irate.

Ray claims that evolution is “just a theory” and that there's “no species to species transitions in the fossil record.”

Oh the willful ignorance.

*Takes a shot*

Ray then vacillates about “kinds” and how he has no reason to believe in evolution because the Bible doesn't say so. As much as I've debated and watched Creationists, it still amazes me that they obsess themselves with “Truth”, yet can't be bothered to pull their heads out of the Bible long enough to look at reality.

At 5:11, Ray says something amazing
You can tie me in knots with evolution, but I don't believe it.
Translation: All the facts of the world could be against me, but I won't believe it.

This comes right down to the core of Creationist belief. Evidence and reality aren't important to them. This is why we must keep these people out of schools. They're dangerous to knowledge.

Ray then equivocates about TF's “faith in the word of man.” No mention of all the evidence. It can all be lumped together as “faith” and then compared to the “faith” of having absolutely no evidence at all.

TF goes on to give a functional definition of speciation so Ray can't wiggle out of it anymore. He then gives an example of some salamanders that are genetically isolated by a mountain range who can no longer inter breed. Ray claims it's “not evolution” and that the salamanders “have an infertility problem.”

Wut?

Ray even admits that you can breed dogs far enough apart that they can't interbreed, but that has nothing to do with evolution.

*headdesk*

TF points out that that is speciation and Ray even admits it. But then demands something “not reproducing after its own kind.” Whatever the hell a “kind” is.

Ray admits that, at that point, “you need time.”

TF explains that, given geological time that's not a problem. Ray keeps on with the equivocating about belief and when TF reminds him that a four and a half billion year old Earth is what the evidence supports, Ray just responds with, “So you believe.”

“Yep. Damn the evidence. If I can just pretend it's 'faith' or 'belief' and drag them down to my playing field, I can win.”

It really is futile to argue with these people (for the sake of convincing them. I think it's perfectly reasonable to debate them to show others just how intellectually challenged they are). As the saying goes, “Don't argue with an idiot. They'll drag you down to their level and beat you with experience.”

PART 8

To start off this part, Ray invokes Pascal's Wager. TF's response is one of the cleverest I've seen. He points out the premise is that the consequence is infinitely bad, such that we should believe in God even if it's the slightest chance that he might actually exist.

TF poses another such scenario: That of a rhino running around at the speed of light. If someone gets hit, relativistic effects would be such that they'd be stuck in that moment of agony for eternity.

Ray's response is that “the chance of that happening are totally unreasonable.”

Way to miss the analogy, Ray.

He can't actually consider how unlikely his God is because “this creation screams to me there's a Creator.”

But as we've already seen, Ray hasn't looked around enough to actually make an honest statement about whether it's possible to explain “creation” without a “Creator.”

Since Ray keeps hammering on about the Bible, at 6:17, TF pulls out his bible, stuck full of little blue sticky tags.

PART 9

Ray says that it's impossible to understand the Bible without the holy spirit. In other words, you have to accept it as true without question, before you can see it's truth. I'd think that an all powerful God would be able to come up with a better method of communication than that.

At one point, Ray acknowledges that there's a lot of things in the Bible he doesn't understand. Yet he continues to have unyielding faith in it? And he claims to preach it?

CONCLUSION

Overall, I don't think Ray makes a single salient point without having to resort to “the Bible says so.” Given he has to rely on this every few minutes, I think it's safe to say that Thunderf00t completely humiliated him. Of course, those that think such answers are acceptable will disagree.

EDIT: Looks like I was right. VenomfangX is back and adding his worthless, hypocritical, .02 Willing to bet my comment doesn't make it through "moderation".

Monday, July 20, 2009

Tuesday, July 14, 2009

Harry Potter!

My girlfriend and I are at a midnight showing of the new Harry Potter movie. The theater was nice enough to seat everyone now instead of making everyone sit in the halls. But they haven't been nice enough to turn on the overhead lights so I can't read the book I brought. And there's 2 hours till the movie starts.

Thus far, my girlfriernd and I are about the oldest ones in the theater. Not too many people dressing up, which makes me sad. I miss the Star Wars premiere when almost everyone was dressed up. Even the bad costumes were fun.

More Science Surveys

The Pew Institute has a new poll regarding scientific literacy and acceptance.

In general, it's more of the same things we've seen before:

Americans like science.
But they don't understand it.
People with more education understand it more.
People with more religious tendencies understand it less.
The media doesn't help.

However, there's some things that surprised me:

The majority of non-scientists feel government funding is “essential” to research. Granted, it's not a whopping huge majority (only 60%) but at least there's more people out there that realize this than don't. Why? The poll shows the majority of people think that scientific funding pays off in the long run. As can probably be expected, Democrats felt this more strongly (80%) than Republicans (68%).

Another somewhat surprising finding was that the most knowledgeable demographic was the 30-49 age bracket. Out of 12 questions, this bracket averaged 8.5 correct; A full question better than my own demographic (18-29) and notably better than the 50-64 bracket which only got 7.8 questions right on average. Was there something better about that group's education? Or is this just a demographic that tends to stay better informed? Amusingly, the only question my age group did do the best on was the “which of the following is no longer considered a planet?” question. I suspect it may have something to do with the “When I was your age, Pluto was a planet” Facebook group.

One question I've never seen before on these polls asked scientists why they chose their career. I was pleased to see that 86% of scientists answered that solving intellectually challenging problems was very important to them. Only 4% said the money was important.

Not only does the general public not know about the science itself, but this poll also showed they were pretty deaf to the oppression of science under the Bush administration. More than half (55%) of scientists heard “a lot” about it, but only 10% of the public was aware. Among those that did hear, 77% of scientists felt it was true, compared to 28% of the public. As expected, 77% of scientists felt this occurred more frequently under Bush than other administrations while only 28% of the non-scientists.

Of course, what would a poll on science be without the evolution question: Among scientists, 87% say they “think that humans and other living things have evolved due to natural processes”. What about the other 13%? Sorry creationists. Almost all the rest are theistic evolutionsts. Only 2% actually believed humans were created in their present form (compared to 31% of the public). Happily, the younger generation seems to be more accepting of evolution. A total of 61% accept evolution (including theistic evolution). This falls about 5% per 20 year age group.

Disbelief in global warming, rejection of animal research and stem cells, fear of nuclear energy, and vaccines are also starkly highlighted as being far less supported by the general public than scientists. Fortunately, a strong majority (69%) of the public still feels vaccinations should be mandatory. I'd be curious to see if/how this has changed over time.

However, the public still remains positive about science, rating scientists as the #3 contributors to the well-being of society (behind the military and teachers). Humorously enough, that ranks us well above clergy and journalists (42% of those attending religious services say their clergy brought up science or scientific findings although the majority said that these references were neutral). As such, I find it very ironic that so many Americans get their science from clergy members and journalists.

But what are scientists trying to do to fix this? Sadly, it looks like it's not much:

While 87% often to occasionally talk with non-scientists (which I presume could also include their spouses or friends) about science, other means are far less common. Only 3% of scientists talked with reporters often (20% occasionally) and 2% blogged (5% occasionally). I'd like to see an break down of the frequency on the journalists by age. I'm willing to bet younger scientists are more willing to talk to reporters but quickly become disillusioned by having their work mangled.

However, one of the things I found the most disappointed wasn't in the poll itself. It was in the commentary. The commentator had this to say:
respondents did far worse on more complex science questions. Only slightly more than half of all public respondents (54%) knew that antibiotics do not kill viruses along with bacteria, and fewer (46%) understood that electrons are smaller than atoms.
I was disappointed enough when a poll showed that nearly half of Americans didn't know how long it took the Earth to orbit the Sun and nearly 20% though the Sun orbited the Earth. Those are pretty basic questions. But then again, so is knowing the parts of an atom. It's not even high school material. And here we have the CEO of the AAAS calling them complex?!

What happened to our standards? If junior high material is can be considered "complex" it's no wonder we're doing so poorly.

Monday, July 13, 2009

Stars, Planets, and Metal

Blogging on Peer-Reviewed ResearchOne of the characteristics of most stars with planets is that they tend to be towards the higher end of metallicity (they have more heavy elements). This should make sense since planets are thought to have rocky cores and you can't have a rocky core without heavy elements.

So what happens when a study of low mass stars in the nearby galaxy shows that all the M class stars are metal poor?

Obviously something is seriously wrong. There's two ways this could be taken: Either the study is wrong, or our theory of planetary formation has a major flaw in it.

Much to the disappointment of young Earthers, it's much more likely that the study. The reason is that for M class stars, finding accurate metallicity is not an easy task. To understand why, let's take a look at the ways we measure metal content of stars.

The most accurate method is via spectroscopy. This method is accurate because you can get the relative strengths of all the elements present by looking at the depth of their absorption lines. That's very nifty since the way we calculate metallicity relies on those ratios.

But the difficulty with all spectroscopy is that it must be performed on each star individually, unlike photometry which allows for quicker data, but with larger errors without careful calibration.

Fortunately, there exist photometric methods by which we can determine metal content. In the photometry I talked about in the post I just linked to, the filters used are carefully selected to avoid as many of the absorption lines as possible to get accurate measurements of the blackbody spectrum. However, if we instead choose filters to hit the pits of these absorption lines for the elements we're interested in, we can use those to determine our metallicity.

The trouble is that for small, cool stars, like the M class stars in question, there's lots of absorption lines. In fact, there's so many, there's almost no distinguishable continuum. Lines can overlap which makes spectroscopy, let alone photometry, exceptionally difficult.

To help try to improve things, the authors of the study used the fact that there's a relation between how much metal a star has and how much it's moved off the main sequence (metals tend to make a star slightly redder and scoot it right on the HR diagram). Piecing this together with photometric data, they argued that they had reliable metallicity estimates.

However, a recent paper is suggesting that the estimates may not be so reliable after all. It tested the older study to see if it could accurately estimate the metallicity of several stars for which they had higher quality measurements. The new study found the old significantly underestimated the metallicity!

Whew! Planetary formation theory is safe!


Bonfils, X., Delfosse, X., Udry, S., Santos, N., Forveille, T., & S├ęgransan, D. (2005). Metallicity of M dwarfs Astronomy and Astrophysics, 442 (2), 635-642 DOI: 10.1051/0004-6361:20053046

Johnson, J., & Apps, K. (2009). ON THE METAL RICHNESS OF M DWARFS WITH PLANETS The Astrophysical Journal, 699 (2), 933-937 DOI: 10.1088/0004-637X/699/2/933

Saturday, July 11, 2009

WTF Spencer, Iowa?

Up in Spencer Iowa, a small town's school board is doing something monumentally stupid: They're trying to shove religion back into schools. And they're not even being subtle about it.

The draft resolution reads like typically uninformed religious propaganda. It starts off requiring that staff and students be granted rights they already have:
School will not discriminate against private religious expression.
School will educate about, not indoctrinate religious faith.
*headdesk*
Students have always had the right to private religious expression. It's when they start doing it publicly, in a manner that disrupts the curriculum or the academic environment that it becomes unacceptable.
Schools have always had the ability to teach about religion. This is something the religious right frequently whines about because to teach about it, means we don't leave out the things they'd rather not have people know.

But it doesn't get any better.
Promote dialogue between schools and community concerning faith.
Yes. Invite sectarian groups to proselytize. Smart one there. And who gets to pick which groups are invited in to do this?
Create a climate of academic freedom concerning faith issues.
This idea sounds wonderful, but how fairly will it be applied? I remember a few years ago a similar notion of allowing religious groups to distribute “backpack mail”. But as soon as a Pagan group wanted to use it, it drew complaints.
Allow for student and employee religious expression within the law.
I feel pretty repetitive here, but students do have this right. Teachers, not so much. If the “within the law” statement is actually upheld, then this resolution doesn't actually mean anything.
School will neither promote, or disparage religious faith.
Which isn't never been allowed to in the first place! Why is this crap included in here? I think it's pretty obvious: A critical analysis of these people's religions and the history of their religion doesn't necessary cast it in a positive light. That's not disparaging it. It's being honest about it. But such people are so thin skinned that they can't tell the difference anymore.

The next section is “Definition”. The one for religion is stupidly vague:
Religion-a specific system of belief which may or may not include a deity, is not limited to orthodox belief systems or practices.
Oh look! Words to equivocate with! Let's not define the difference between “belief” based on evidence and “belief” based on blind faith.

The next one is even worse:
Evolution – The belief that an unguided process of mutation and natural selection resulted in the existence of life on earth.
I can guarantee no one with any scientific knowledge beyond a basic course helped write this crap. Evolution is not unguided. Natural selection is a powerful guiding force. Evolution does not have anything to do with the “existence of life on earth”. It only discusses the diversity.

The section on “Graduation exercises and other Extra-Curricular Activities” is nothing but things that have been ruled against by courts in the past:
a. Content of speeches by private individuals will not regulated on religious content.
b. School will permit the graduating class to choose whether to have an invocation and or benediction to be given by student volunteer in a non-proselytizing and nonsectarian manner.
The first one is basically saying that the school will not keep out preaching. The second contradicts the first saying that proselytizing is not ok. Make up your minds guys. It even contradicts itself by allowing for a “nonsectarian benediction”. While a benediction can be just a general well-wishing, given the title of the document (Religious Liberty), it's safe to assume that it's talking about a religious one.

Like the school I mentioned before, this school is trying to allow for distribution of religious materials too:
a. Religious materials may not be singled out for specific regulation based on content.
b. Students may distribute religious materials at reasonable times and manners designated by the school.
Again, something that sounds good, but just wait till someone with views they don't want tries to apply for the same rights. As for the second statement, students already have these rights, but it's pretty worthless anyway. Unless you want trashcans full of Chick tracts.

The section on “Religion in the Curriculum” is just a mess.
1. Curriculum areas that overlap religious faith shall demonstrate respect for affected religious convictions.
2. Electives to be offered at Spencer High School:
  a. The Bible in History and Literature
  b. Critic of Darwinism, a scientific approach. (provide a balanced review of evidence for and against the theory of evolution, using texts which include “Darwin’s Black Box” by M. Behe)
The idea that topics that may overlap must “demonstrate respect” is just code for “tiptoe around anything we don't like to hear” which destroys the stance of neutrality they're pretending to create. As far as the elective courses, the first one is fine. The second is, well, at least they're admitting the “criticism” of religion is a religious exercise. But seriously, Darwin's Black Box!? That book's been torn up and down so many times now it's not even funny. That's hardly “balanced”. Nor does “Darwinism” even exist beyond a silly Creationist strawman!

And just so the whole thing ends on a stupid note:
Teaching about the holidays. Discussion of the significance in an objective and historical nature will be allowed.
Sure. So they're going to admit that every Christian holiday is a rip off of other religions? Yep. Thought that one through real well...

HT: Stupid Evil Bastard

Friday, July 10, 2009

Planets and Shadows

Blogging on Peer-Reviewed ResearchLast year, I blogged about why catching stars forming is a tricky proposition; They're surrounded in gaseous nebulae that makes trying to observe the act a bit like watching a sports game from a plane flying through the clouds. You just can't see through it all.

In general, this should hold true for planets. Until the star clears out the dusty disk, the planets will remain hidden, even if we could spatially resolve them. So a paper talking about forming planets with “Observable Signatures” in the title caught my eye.

In this paper, the author explains something that, at first glance, is actually counter-intuitive: These dusty shells may help find newly forming planets. The reason is that, as planets form, they will slowly accumulate the material around them. In the vertical direction, this has the effect of making a “dimple” in the proto-planetary disk proportional to the planet's accumulated mass.

According to the author, the dimple will appear observationally as a “shadow”. She doesn't completely explain why this is and it seems somewhat strange to me. The reason is that “shadows” are usually caused by something that blocks light. Although the forming planet would cast a (relatively) small shadow that would be lost in the disk, it's not at all clear what would cause a shadow in the dimple.

Rather, I suspect a better word choice would have been to say there would be a “darkening” in the dimple. This would make more sense to me, since the dimple would be a lower density and have less material to scatter light propagating along the plane. Less light means that, relative to the rest of the disk, it would appear darker. Thus, I'm pretty sure that's the actual mechanism at work here.

But there's another interesting component: On the side of the dimple that's further from the parent star, there's a brightening! Weird huh?

This again, is not well explained in the paper, but I suspect the reason for this has something to do with the angle at which the photons coming through the disk are striking the side of the dimple. Either that or it's the opposite of the darkening effect where suddenly the boost in numbers of photons that were allowed to flow relatively freely through the empty space created by the dimple are suddenly again encountering a relatively dense medium again.

Regardless of how these effects should be created, planets should show a dark spot next to a brighter spot with the sizes proportional to their mass. But should these be observationally detectable?

According to the paper, yes. These features would be most readily observable in the visible to near-IR bands. The real limiting factor would be how well we're able to spatially resolve these dimples. Obviously, the further away a system would be, the smaller it would appear. Even for the largest planets simulated (50 Earth masses), the dimple is about 3 AU across. That means that we'd need to be able to resolve half of that to see both the darkened and lightened portions.

Tossing that into the small angle equation and assuming a fairly typical resolution for a good telescope of 1arcsec, we get that we should be able to observe these systems out to 3.1 x 105 AU or 4.9 ly.

Eep!

That's not very far at all! In fact, the only stars that fall in that range are the stars in the Alpha Centauri trinary star system. The next closest one after that (Barnard's star) is 5.9 ly away!

The Hubble can get down to ~0.1arcseconds of resolution, which would mean 10x further, but there's still not really any star forming regions within 40 ly.

So ultimately, while this technique is interesting it doesn't seem the least bit practical with the current generation of telescopes.

Jang-Condell, H. (2009). PLANET SHADOWS IN PROTOPLANETARY DISKS. II. OBSERVABLE SIGNATURES The Astrophysical Journal, 700 (1), 820-831 DOI: 10.1088/0004-637X/700/1/820

Anime Review – Planetes

No. I didn't spell the title of the series wrong.

Planetes isn't a series of which many people have heard. It received the prestegious Seiun award for the manga in 2002 and for the anime in 2005 (the famous series Cowboy Bebop won this award in 2000). Even among rabid anime fans, it's gone largely under the radar. I suspect this is because it doesn't fit the norm of being ridiculously over the top; There's no giant mecha, no magic powers, no crazy transformations, no ninjas.... oh wait. There's ninjas. But not in the normal anime way....

Instead Planetes is a very subdued series that focuses more on character development and complex yet subtly highlighted issues rather than the in your face action. The series takes place in the near future when space debris has reached a level so critical that it's requiring international clean up efforts. The main characters in this series are debris haulers in charge of this zero-G cleanup.

For an anime series, the science is unexpectedly good. There's frequent talk of transfer orbits, Van-Allen Belts, relative motions, dangers of radiation sickness, muscle degeneration in weightless environments, and other things that, in most series, I'd expect to be filled with techno-babble. But in this series, it's apparent the writers did their research and yet, it's not even boisterous about it. Whereas many series that have to do similar research for accuracy will take the time to show it off (usually by having awkward lines of someone having to explain the concept to someone that should already understand it), Planetes drops it in seamlessly, merging into an unusually harmonious background.

As I mentioned, the series manages to touch on many very human themes throughout the 26 episode run. It tackles the place of humanity in the universe, class divisions, terrorism, the difference between ambition and greed, and isolation.

It's one of the best series I've watched in a long while. If you're into anime and haven't seen it, I'd recommend picking it up when you have the chance.