Thursday, June 28, 2007

Stormtroopers can't shoot - but they can do science

Crystal Lake Il, is getting ready for their annual Gala Parade coming up this Sunday. And it looks like they'll have a very cool float. Apparently one of them is going to be a large scale replica of Darth Vader's TIE Fighter.

However, that's about all I got out of the article that made sense. It also says:
Between 15 and 20 people from Illinois, Indiana and Wisconsin are expected to don the costumes of three factions of Star Wars characters and march along the TIE fighter.
Three factions of characters? You mean, the Light Side, the Dark Side, and then the oft ignored by ever so mischevious in a lighthearted manner Grey Side?

I suspect what they really mean is that three chapters of the 501st Legion (a dedicated bad guy Star Wars costuming group) from the three states will be showing up.

But the part of poor journalism that really cracked me up was the next part:
Empirical Stormtroopers will march with rebel allies and lightsaber-wielding Jedi Knights, Whitaker said.
Empirical stormtroopers? As in they are guided by experimental data? Man. No wonder the Empire had such a hard time. They filled their battlestations with a bunch of scientists!

Wednesday, June 27, 2007

Stellar Evolution: Variables and Astroseismology

So far in this series on stellar evolution, we’ve talked about things that we don’t really observe happening in real time. Rather, models show that things happen over time, and we have a series of stills to compare it to because, typically, things take a very long time.

But not always.

Sometimes things can happen very quickly. And if our models are to really be any good, they must be able to explain these events too.

Perhaps the most common set of events that we can observe on short timescales is that of variable stars. This is a very large grouping, including stars that change their brightness in less than an hour to a year or so. These wonderful stars are extremely important to astronomy. Certain types are used to measure distances and many can be used to test our models of stellar evolution.

In astronomy, there are three main types of variables that are often discussed. Regular variables are stars that change their brightness in a regular fashion. Irregular ones are, well, irregular. The third type is known as cataclysmic variables. This group includes stars which explode as novae or supernovae.

For the first two groups, there are a very large number of sub classes, typically named for the first star of the type identified as variable. For example, it was long ago known that the star Delta Cephei varied in a regular manner. Thus, stars that were discovered later which varied in a similar manner were labeled Cepheids.

Cepheids are especially important in astronomy because they’re wonderful distance indicators (their period is related to the average brightness). However, as with everything else I’ve discussed in this series of posts, models better be able to account for why these stars are changing like this.

It turns out that there’s a region on the H-R diagram where models tell us stars should become somewhat prone to instabilities. It’s aptly named the instability strip. Cepheids fall right smack in the middle of it and many of the other types do as well.

As the star evolves across the H-R diagram heading towards the Red Giant Branch, some layers of the star become more opaque than normal (less light is getting through). Since light is what carries the energy out of the star, this creates a dam, blocking the energy which causes an increase in temperature and pressure. This buildup pushes these layers outwards. When it expands, it cools, and the primary cause of the blockage (ionized electrons) is removed. But now the star is overextended and begins to collapse again. The collapse causes the temperature to increase again, reionizing the electrons and beginning the process again.

That’s the simple description but works pretty well for the better-behaved Cepheids. For the rest, many patterns can be accounted for by adding more layers of ionization causing different pulsations as well as shock fronts and other mechanisms.

So for at least one type of variable star we do a pretty good job modeling what’s going on. And when our models can jive with observations, that means it’s a good model.

Meanwhile, some variable stars can be used the other way around. Instead of matching the model to the star as we’ve been talking about here, we can use the stars to make the model.

Here on Earth we’re all quite familiar with the practice of seismology which uses shock waves traveling through the Earth and bouncing off the various layers to figure out what sort of stuff is on the inside (sadly, it’s not a cream filling). This works because seismic activity such as the crashing of tectonic plates can create strong shock waves of various sorts.

It turns out that stars do the same thing although through different mechanisms. I’m not going to bother discussion the mechanisms because that’s beside the point. The point is that stars vibrate and by studying those vibrations, we can look inside stars.

And guess what! What we find matches pretty well with our models. One particular class of variables that is commonly used for this practice (known as astroseismology) is known as Delta Scuti stars. But really any star that vibrates and we can get accurate data on it’s radial velocity to an accuracy of a few meters per second is susceptible to this method. In fact, it was originally performed on the sun via helioseismology.

So, yet again, models and observations fit hand in hand, giving us a clear picture of how stars work and evolve. In my next post on stellar evolution, I plan to look at the last stages of a star’s life, which is one of the most important to us because, as Carl Sagan put it, “We are star stuff” and the heavy materials that comprise our bodies had to be cooked up in these late phases. That’s really the last topic I planned to cover on stellar evolution so I’ll probably make one more post as a grand summary and conclusion.

Friday, June 22, 2007

"We're going to need a bigger boat"

For the first 3 years of my college life, I attended what is now Missouri State University (was then Soutwest Missouri State). For the most part, I don't miss it. However, aside from catching up with friends from there, there are the occasional things that MSU does that are pretty damned cool.

This past semester, MSU's Pastafarian group got together at the public forum on campus (where Brother Jed can often be seen), to construct a gigantic cardboard pirate ship and hold "Noodlefest".

Here's some pictures from the event take by friend Emily Sommers.

21st War of the Lilies

For those that don't know me too well, I do occasionally take time off from being an evil atheist out to thwart theists by pointing out their pseduoscientific nonsenese "theories" and engage in other hobbies. One of those hobbies is swordfighting as a member of the Society for Creative Anachronisms.

This hobby was the primary reason for my recent dry spell of posts (the secondary reason being there wasn't anything I felt like commenting on). Upon returning home from school, much of my time was spent preparing for the 21st War of the Lilies. I spent nearly 2 weeks at the sewing machine making myself a well dressed medieval gent. From there, I headed to the main event just north of Kansas City, for the main event. Five days were spent camping and on the field in armor in the midwest heat and humidity.

The friend that accompanied me took lots of pictures, and you can check out the whole gallery here. There's 153 pictures in there, so it might take awhile...

Right thing. Wrong Reasons.

Over at Pharanguyla, PZ bemoans a church forcing the shutting down of library summer programs for what they percieved to be promotion of witchcraft and drug use.

Some programs involved making tie-died T-shirts ("Promotes the hippie culture and drug use"), or Zen garden and Yoga classes ("promoting other religions"). I would agree that these are completely harmless. Tie-died shirts no more promote drug use than having long hair. I suppose the leaders of this church would encourage sumptuary laws.

Zen and Yoga are indeed derived from other religions but are not approached from a religious standpoint. Rather they are approached from the perspective of relaxation techniques and physical therapy respectively. This is much the same as approaching the bible from the perspective of a historical document. Unless you're wanting to be converted, it should have no effect.

Meanwhile, I can't say I'm sad to see other programs go. The library was also offering classes in astrology, palmistry, numerology, and tarot card reading; All classes full of vacuous nonsense. These classes have no place being funded by public tax money, especially in what should be a place of knowledge.

But if you're going to force a library to cancel its classes, don't do it because it "promotes other religions". Do it because they're 100% grade A bullshit.

Wednesday, June 20, 2007

"I think we're being followed..."


The NY Times has a picture up of the shuttle leaving the space station. Over the right booster we can see an object that's supposedly the space station. But us geeks know what it really is.

Pareidolia: part n + 7

Looks like Phil beat me to one, but Jesus has appeared in refracted light on a Chruch ceiling. At least he's got the right address this time.

Mother in the Sun

It seems a 17 year old girl in South Africa has been seeing visions of the Virgin Mary and has been telling other people how to do it as well. Just look directly into the sun.

One person has already severly damaged their vision and now the Catholic Church is telling the girl to stop recieving pilgrims and telling them to look at the sun.

What should be an example of common sense is sadly, another example of how religious fervor can turn people into complete idiots.

Friday, June 08, 2007

Pareidolia: part n + 6


It's been awhile since I've seen an article of faces appear on muffins or trees but it's happened again.

But this time, it's not Jesus. It's the ghost of a small town mayor.
But not everyone is convinced it looks like Stephens.

"I see Jesus," said Cathy Sansone, the membership director at the health club who says any resemblance to the late mayor is simply the "power of suggestion."
Oopsie. Maybe it is Jesus. Or maybe the health club membership director should listen to the words coming out of her own mouth instead of exempting anything religious from even the most simple of critical analysis

How does the garden grow?

It looks like everyone's talking about the new Gallup poll that shows more of what we already knew: Nearly half of America is filled with evolution denying idiots.

But absent from the discussion in many other blogs is something else that I think needs to be pointed out and considered.

Question 24 asked Americans how familiar they were with both evolution and creationism. In each case the total saying they were familiar was about 85%.

I'll go ahead and call this one: Bullshit.

I've been discussing evolution as well as many other science topics for several years now, both in person and in online discussion forums. The number one thing that has always struck me is that, in most cases, those who criticize science can't even correctly define what they're criticizing!

Even in forums which are dedicated to people with strong interests in science, I still see the most basic of errors. I found myself correcting the same errors so frequently that it turned into my 4 Big Bang Common Misconceptions post last summer.

Long story made short: Americans think they know a lot more than they do. However, if we made them go back and take a high school exam, I doubt even 10% could pass them. In fact, the problem is so bad, that Fox has an entire TV show showing that adults can't answer the same questions as 5th graders.

So what we really have is a bunch of arrogant Americans that think they know what they're talking about, trying to write policy about things they can't even remember the definitions of from elementary school. A fertile soil of ignorance, watered with religious superstition, and bathed in the sunlight of assumed knowledge is what has led us to the deeply rooted weeds we have today.

The question is what to do about the weeds. I think the best answer is to attack it on each of the three prongs. If we can eliminate the soil, it will have no place to grow. But that's a huge task. Schools are already working extremely hard to educate students and ultimately, I think they do a pretty good job. As I see it, the trouble isn't the schools so much as the cultural attitude that what you learn isn't applicable to everyday life and can be thrown in the mental compost bin as soon as you get your grade.

But once you've composted something, it starts decomposing and turning into that slimy mess that all blends together. That's where you get weird mixtures of things like people thinking the big bang says there was "nothing" and was an "explosion", or that evolution "says we came from monkies". All those words are in there somewhere, but it's all jumbled and mixed together. But again, that's not the fault of the schools so much as cultural attitudes which are going to be nearly impossible to change. Perhaps schools could make the knowledge they instill a little less mental-degradable, but I think it's a stretch to expect them to start handing out intellectual styrofoam.

As far as getting rid of religious superstition, that's something else that's not about to change any time soon. People like Dawkins are slowly starting to unravel it, but I doubt that it will ever be gone in any real sense. Merely changed.

But what about the last case: Trying to prevent the arrogant attitude that Americans have that presumes that a high school diploma means they're "very familiar" with advanced topics? This is one area that I think there is a great deal of progress to be made. High schools should stress (especially in the last year) that this is just the beginning of the path to intelligence. They are merely the smorgasbord of introductions. But nothing beyond that.

Spending 12 years in the educational system seems like a long time, but given that those that are truly the experts can dedicate their entire lives to a single sub-field, 12 years sampling 6 different topics a day, doesn't make one qualified for much of anything. Instead, we should instill a sense of humility in students before turning them loose in the real world. And for those that don't learn their lesson, then we shouldn't play nice and pander to their nonsense.

When people start realizing that they don’t know what they’re talking about, they won’t feel the need to start trying to create public policy that perpetuates their misconceptions. Instead, they will be forced to rely on experts. I make no claim that the experts are always right, but at least there would be far less time wasted on things we know are wrong.