Blogs / Bad Astronomy

Man, I gotta get me a can of this stuff:

That would be really useful in June!

The spiral galaxy NGC 2397 is more than just a pretty face… though it is a very pretty face:

Spiral galaxies have lots of gas and dust in their spiral arms which actively form new stars. Some of these stars are very massive and bright, and can be seen as individuals in Hubble images like this one. Massive stars don’t live long, exploding as supernovae after only a few million years. Images like this one can prove invaluable when such a star explodes; we can go back and look for the star itself in older images and learn more about it.

As it happens, the astronomers taking this image of NGC 2397 caught a supernova just as it was starting to brighten! That’s a cool coincidence, and very helpful; observations of supernovae before they get really bright are hard to come by.

So where is it in the image? It’s not either of the two really bright stars you see; those are both nearby stars in our own Milky Way. Actually, the star would be impossible to find without already knowing where it was (click to embiggen, as usual):

It doesn’t look like much… but that’s because it was caught early. Supernovae explode with so much energy that they can actually equal the brightness of an entire galaxy! So no doubt a few days later this nondescript star located in a galaxy 60 million light years away became a heckuva lot more noticeable, at least to any aliens local to NGC 2397. From Earth, it never got terribly bright, only about magnitude 15.6, or 1/10,000th as bright as the faintest naked-eye star. Still, that’s bright enough to be well-studied.

One other thing: once a star explodes, it’s very hard to know much about what it was like before the titanic event. The astronomers who made this study of supernova host galaxies have made an amazing discovery: stars as lightweight as 7 times the mass of the Sun can explode! That’s lower than previously thought, and makes me wonder; perhaps the star in that case had erupted previously, losing most of its outer layers, exposing just its core. When that exploded, it would be an underluminous supernova coming from what looks like an undermassive star. In reality it started out very massive (20 or more times the Sun’s mass) but lost a lot of weight on its way to exploding. I couldn’t find a paper online with any specifics, so if anyone knows about one (the lead author is Stephen Smartt) please leave a comment! In the meantime, I’ve emailed him and I’ll post a response once I get one.

My very good friend Lt. Colonel Hal Bidlack is running for Congress.

He’s running for a seat in the House of Representatives for Colorado’s 5th District. This is Colorado Springs, home to conservative icons like the Air Force Academy and (shudder) Focus on the Family. This is not a stereotypically progressive place.

Hal’s running as a Democrat. And I think he can win.

The incumbent, Doug Lamborn, is a Bush lackey, and a neocon of the worst sort. His votes on the Floor align with whatever Bush wants virtually every single time. That will be quite the dead weight come November. His voting record speaks for itself. The guy has to go.

Hal, on the other hand, is someone who can think for himself. As he said to me recently, he’s a western Democrat: he thinks the government should stay out of our business when it doesn’t belong there, that the Second Amendment is a pretty good thing, and that we shouldn’t spend money when we don’t have it. Radical, eh?

You can read all about Hal’s excellent qualifications on his Wikipedia page and his campaign site (you can join his fan base on Facebook, too). But they don’t tell you everything about him, of course.

I met Hal at Randi’s first Amazing Meeting in 2003. He struck me as an upright guy: smart, funny, warm, and, oddly, polite. We hit it off pretty quickly. He was the MC for the meeting, and during a panel I was on he gently teased me, and I gave it right back to him.

But it was what happened earlier that solidified Hal in my mind. About an hour before I was to speak, the Space Shuttle Columbia broke up upon re-entry over Texas, killing the astronauts and putting NASA into a tailspin itself. I was rocked, as was everyone, of course.

Hal was asked to announce this at the meeting, minutes after it happened. With only moments to prepare, this is what Hal said:

The space shuttle Columbia was lost a few minutes ago. At 200,000 feet over Texas, NASA lost contact and images from the ground show the shuttle breaking up and impact is reported north of Dallas.

Now listen to me. I’m a career military officer. This is a tragedy. But these people were doing exactly what they wanted to do, in exactly the place they wanted to be. When Dave Scott set foot on the moon on Apollo XV he said, “Man’s fundamental nature is to explore, and this is exploration at its greatest.” Gus Grissom gave an interview a week before the fire on Apollo I and he said, “if there’s an accident, for God’s sake, don’t let it stop the program.” This is a tragedy, but they understood, and that’s what we do in the military.

We’re going to take an hour break. We’ve got TVs in the lobby. We’re going to try to put a TV into this signal and of course you can go up to your rooms if you wish. And in an hour; let’s call it 11:30, that’s an hour and 15, we’re going to continue the conference because I believe that it would be an insult to their memory to deny this audience the information that we want to give it. We can mourn, and we shall, but with dignity and grace, and remember that the space program is an amazing thing. I know astronauts. They were where they wanted to be.

Hal Bidlack stood up and gave that speech without notes, just saying what needed to be said. It speaks of a sharp mind, a grasp of reality, as well as a human viewpoint that showed in its own way our ability to overcome even major obstacles and succeed. In that short speech he was able to convey the sorrow we would all feel once the shock wore off, but he was also able to turn it into inspiration.

That’s just how Hal is.

I don’t live in Colorado’s 5th District, so I can’t vote for Hal. If you do live there, I encourage you to investigate the issues and vote as you see fit.

But if you don’t live there, you can still help put a good man — one of the few — into Congress. If you are an American citizen, please consider donating to Hal’s campaign fund. You know how very rarely I ask for something like this, so I hope you understand how important this is.

Hal deserves to get a chance to make things right in this country, just as much as we deserve to see them made right. That’s why I am officially endorsing Lt. Colonel Hal Bidlack for Congress, representing Colorado’s 5th District.

Run, do not walk to the ESA website and download the magnificent image of Hebes Chasma on Mars:

This is an extremely deep chasm (8000 meters deep — that’s nearly as deep as Mt. Everest is tall!) almost smack on the Martian equator, at the northern tip of the grand Valles Marineris, the canyon on Mars that’s as wide as the Grand Canyon is long, and as long as the United States. This image from the high resolution camera on Europe’s Mars Express has a resolution of 15 meters/pixel, so if any martians are playing tennis, you could just make out the court. They even have an anaglyph!

Universe Today (make sure you Digg that article, not mine!), where I saw this first, has more info.

That image is stunning, fantastic. It may even edge out my other favorite Mars picture, and it’s certainly a contender for my Top Ten pick of the year.

Wow.

I just had a problem on my Mac that I could not solve anywhere on the web, but wound up solving on my own. If you don’t own a Mac, then move along, but if you do, this may save you hours of frustration.

I have a Western Digital 500 Gb external hard drive (which I named Colossus for those who get it). It’s formatted as Mac OS Extended (journaled). It came FAT32 of course, but that has issues — like it won’t allow files bigger than 4Gb which is simply stupid. So I reformatted it, and everything has been cool… until last week.

I tried moving a movie file over today by dragging it off the Desktop and onto my external drive, and I got an error message saying Finder couldn’t move it because all or part of the file had a problem. This is the dreaded "Error Code -36" message, which I assume Apple stole from Microsoft because it is a generic message which tells you nothing.

Anyway, I searched high and low on the web for some way to fix this, but nothing helped. I changed permissions, I checked for errors using disk utility, and lots of other things. Nothing worked.

I also noticed that text files moved over just fine. So did an XLS file. Just not AVIs.

I was scratching my head, and then suddenly thought: wait a sec! OSX (I’m still using 10.4 by the way) is based on Unix. I know lots of Unix!

So I opened a terminal and cd’ed to the external drive directory. Everything looked fine. Permissions and everything were set correctly.

What I did next appears to have fixed the problem: instead of using Finder, in the terminal window I used the Unix command mv to move an AVI file from my internal drive to the external. It looked something like this:

prompt%> mv /Users/phil/Desktop/movie.avi .

… which translates to "Move the file from my desktop to the current directory" (remember, I had already cd’ed to my external drive’s movie directory, which looks like /Volumes/Colossus/movies).

That worked. Aha! Maybe the problem was with Finder! So I went back and tried to move another movie file (similar to the first) using drag-and-drop, and this time it worked. W00t!

I’m not sure what was going on; maybe Finder got all bollixed up, and by directly moving the files in Unix Finder was able to find its way back to reality. I don’t know why this worked. But if you ever get the Error Code -36 message, try this. I just made myself very happy after being very sad.

What we we do without the Onion?

The image is old, but when ever does The Onion not become relevant?

I linked to this subtly in my post about my trip to the UK next month to visit Europe’s new particle accelerator, the Large Hadron Collider (LHC), but it deserves more attention.

Two men are suing to stop the LHC from being switched on, saying it may be dangerous and might even destroy the Earth:

But Walter L. Wagner and Luis Sancho contend that scientists at the European Center for Nuclear Research, or CERN, have played down the chances that the collider could produce, among other horrors, a tiny black hole, which, they say, could eat the Earth. Or it could spit out something called a “strangelet” that would convert our planet to a shrunken dense dead lump of something called “strange matter.” Their suit also says CERN has failed to provide an environmental impact statement as required under the National Environmental Policy Act.

[...]

The lawsuit, filed March 21 in Federal District Court, in Honolulu, seeks a temporary restraining order prohibiting CERN from proceeding with the accelerator until it has produced a safety report and an environmental assessment. It names the federal Department of Energy, the Fermi National Accelerator Laboratory, the National Science Foundation and CERN as defendants.

First off the bat, this sounds nuts, but really it’s not so nuts that we shouldn’t look into it. There are two causes for some concern: one is that LHC might create a black hole which would eat the Earth, and the other is that a very odd quantum entity called a strangelet might be created, with equally devastating results.

However, I don’t think there’s anything to worry about. I want to make that clear up front.

The LHC will slam subatomic particles together at fantastic speeds. The collision in a sense shatters the particles and all sorts of weird beasties are created in the aftermath. This give physicists insight into the basic quantum nature of the Universe. The higher the energy of the collision, the more interesting stuff you get. LHC will be the most powerful collider ever built, and is expected to provide really new looks at the quantum world.

That’s what has the two litigators worried.

If two subatomic particles collide at high enough speed, it’s possible that they will collapse into a black hole. If that happens, it would fall through the Earth and, well, you can guess what bad things would happen then^*.

However, studies done by CERN show that the energies generated will be too low to make black holes. Also, due to a weird effect called Hawking radiation, the tiny black holes would evaporate instantly. The two litigants, however, say that Hawking radiation is not an established fact, and therefore we should be more careful. While that’s technically true, they forgot something important: the same rules of quantum physics that make a black hole in a subatomic collision also indicate they would evaporate. So if you’re worried they won’t evaporate, then you shouldn’t be worried they’d be created in the first place.

Same goes for the creation of a quantum strangelet. This is a weird conglomeration of particles called quarks, and if a strangelet comes into contact with normal matter can convert it into more strangelets. The idea is that these can cause a chain reaction that turns all available matter into strangelets. That would be bad.

However, first, strangelets are completely theoretical, and again even if they are real it’s incredibly unlikely they would be created even by LHC. And even if they were created, the chances of them being a danger are very small. A study a few years ago by physicists at MIT, Yale, and Princeton shows this to be the case; as they point out, higher energy particles hit the Moon all the time. If strangelets could be created in this way, the Moon would have converted to a big ball o’ strangelets billions of years ago.

So I think that considering things like this happening is good — after all, we’re walking into new territory here — but in this particular case the litigants are wrong. A lawsuit seems like overkill. In fact, it’s so odd that my skeptical gland was tweaked, and I decided to look into the litigants’ backgrounds.

Walter Wagner apparently has a physics background, but was involved in a similar lawsuit over the Brookhaven collider a few years back, which turned out to be completely baseless.

As for the other, Luis Sancho, he’s, well, how do I phrase this delicately? He’s a bit outside the mainstream. Actually, way outside the mainstream. In fact, totally and way way far outside the mainstream. I don’t think you can even see the mainstream from where he is.

While dismissing the idea of any danger from LHC due to these factors would be an ad hominem and therefore unfair, I think it adds a dimension to this case that’s good to keep in mind.

Again, I’m not worried. I don’t see any basis for their fears, and certainly not for their lawsuit.

So I’m still greatly looking forward to visiting the LHC in April. It’ll be a fantastic glimpse into the next generation of physics, and will open up new vistas for us to explore.

If the court agrees to let it run, of course.