The Disco ‘tute, the ironically described think tank for intelligent design, loves to crow about how there are basic controversies in evolutionary science and that makes it all wrong. However, in the real world, we know that the mouthpieces at DI are overly fond of lying, as has been shown so many times that it should set the whole world’s collective pants on fire.

But there are real controversies in evolution, as there are in any science. An article in ars technica by biologist John Timmer talks briefly about some real issues in evolution, enough to give you a taste of what’s real, as opposed to what the jabbering heads at DI froth over.

Don’t let the antiscientists fool you. As we real scientists who fight them like to say, just because we don’t know everything doesn’t mean we don’t know anything. And we know a heckuva lot more than they do.

Tip o’ the flagellum to BABloggee and cool cartoon artist Matt Andrews.

A lot of you may have already seen this, but a 1200 meter volcano called Chaiten in Chile erupted the other day, blowing smoke and ash kilometers into the sky. It also sparked massive lightning, and the images are incredible:

There are quite a few amazing pictures of the event on Flickr. There is also this astonishing video on YouTube:

Other videos abound as well.

This is the first eruption of Chaiten in almost 9400 years. Small towns nearby have been evacuated, and I haven’t heard reports of anyone getting hurt.

I rather hope we get some images of the eruption taken from the space station. They tend to be rather dramatic.

A Breaking news for sky afficianados post made me sit back and gape for a moment: "Armageddon" and "Deep Impact" came out this summer 10 years ago. Wow. I’ve been mocking the former and hyping the latter for a decade now. Cool.

I use both movies in a general public talk I give about astronomy, showing brief clips that go over mistakes made as well as some rare accuracies as well. I still think "Armageddon" is one of the worst movies ever made, ever, and "Deep Impact", though flawed, is far superior.

But wow, 10 years? BNfSA has some thoughts on this as well, seeing as how the two together have grossed nearly a billion dollars since their release.

It’s enough to make Ben Affleck cry.

On May 25th of this year, the Mars probe Phoenix will land on the red planet. This interplanetary lab may not rove about the surface like Spirit and Opportunity, but it is loaded with experiments to test the polar region of Mars to see if life ever arose there.

The landing site was chosen to be as boring as possible; they want the thing to land safely, and that means a wide, flat area. The chosen site really is dull, but happily Emily found something interesting to say about it: it sports dust devils. And she has a very cool image to back it up.

I’ll be writing more about Phoenix as landing time approaches. Stay Tuned, but check with Emily’s blog to get details more often. This is her territory more than mine.

The folks at the NSCE and Expelled Exposed have done it again: made a great instructional video about evolution. This one is how an eye can evolve, and is so easy to understand that it should be shown to every single school student in the country, and indeed the world.

Update (5/7/08): The image I had posted originally was distorted due to the wrong picture being made available to the press (like me!). I got a nice email from Joerg Dietrich, one of the astronomers who took the data, with a link to the correct image. I have updated both the image and the link. Sorry, and enjoy!

We’ve known for a long time that most of the Universe is invisible. 72.1% of it is dark energy, about which we know very little. 23.3% of it is dark matter, which was only recently tagged for real and for sure; we still don’t know what particles make it up, but we’re on the verge of finding out.

Normal matter — us — makes up just 4.6% of the Universe’s energy and mass budget. But here we are! At least, here we mostly are: actually, we only see roughly half of the normal matter in the Universe. Stars, galaxies, and warm-to-middling gas aren’t too hard to spot in general, but they only make up about half of what we expect to see of normal matter.

Where’s the other half?

Let’s turn the wayback machine to about 13.6 billion years or so ago. The Big Bang is old news at this point, but the first stars have yet to be born. Matter and energy are mixed everywhere, but some of it is different. What we now call dark matter is starting to clump together through gravity, forming long sheets and filaments far bigger than any galaxy we see today. This forms a grid, a framework, upon which normal matter starts to fall. Eventually, galaxies and clusters of galaxies and clusters of clusters of galaxies will form along these cosmic skeletons.

Fast forward to today. Bang! We see galaxies everywhere… well, not exactly everywhere. We see them lying in those long sheets and filaments, showing us where the dark matter structures are, like dew drops on a spider’s web.

But that’s just the stars and galaxies, remember? It’s only half. Where’s the other normal matter?

The hypothesis is was that it would be in the form of very hot gas strung out along those filaments as well. Hunting for it would be hard: it would be very diffuse, making it dim, and very hot, meaning it would only emit at short wavelengths, like extreme ultraviolet or X-rays.

Hey, we have telescopes that can see those!

And now we have (and more pictures can be found here). Astronomers upped the odds of finding the gas by looking around galaxy clusters, where it would be denser, and also doing something clever: looking near clusters that are near each other in the sky due to perspective. One would actually be farther away than the other, but peering very nearly along the angle separating them they would look like they’re right next to each other. Since we’d be looking along a long thin cylinder of gas, that would make it appear brighter than if we saw it through its side.

The picture above shows the galaxy clusters Abell 222 and 223, both about 2.5 billion light years away. The visible light image just shows them as clumps of points, but remember: each dot is a massive galaxy like our own! The technicolor bit is from the XMM-Newton orbiting X-ray observatory, and shows the hot gas. Since these are separate clusters, they should be detached from each other. But instead, they’re connected by a gas bridge of ten-million-degree plasma. That’s the missing stuff! That’s made up of baryons; particles like protons and neutrons, atomic nuclei and the like. Look around you: everything you see is made of baryons (and leptons, which include electrons), so this gas is your kin.

It’s a bit more rarified, though: there are only about 30 baryons per cubic meter in this bridge. Good thing it’s big (about 4 million light years wide) and we’re looking down its length! But then, that’s why so much of this stuff is missing. It’s really hard to detect.

According to the models, there is enough stuff in this bridge to extrapolate the existence of the rest of the missing normal matter. Of course, we only have a data set of one, which is a bit rocky, but I suspect more of these will be found now that we know they’re out there.

And may I add, phew! It’s always nice when half the stuff you can’t find finally turns up.

When the Space Shuttle Columbia disintegrated over Texas in 2003, it was a disaster and tragedy for many obvious reasons. One news item that was lost — literally — amidst the wreckage was that some scientific experiments being done were also destroyed.

However, there is a somewhat happier ending for at least one of them. An experiment done on board Columbia was testing certain physical properties of xenon gas. The data were recorded on a hard dive, and it was assumed the drive burned up or was destroyed upon impact along with most everything else from the mission.

However, the hard drive was recovered. Not only that, but the data on the drive were recovered as well! And now, years after the accident, the scientists were able to publish their results, which is rather nice to hear.

I’m not happy with NASA’s direction of late in sacrificing science for ill-advised missions, and I was never happy about the science capabilities of the Shuttle or the space station. But it’s nice to see, in one small way, that some of what science was being done was able to be saved.