Direct Proof of Dark Matter

July 24th, 2007

Chandra :: Photo Album :: 1E 0657-56 :: 21 Aug 06

The issue of the reality of dark matter has kept coming up recently in my life, both in the writing and educational spheres. I recently finished copy edits on the new book (SPIDER STAR will hit stores in March 2008 and I’ll blog about that soon), and dark matter is a central concept. On the educational side, the first LAUNCH PAD astronomy workshop for writers recently concluded and was by all means a big success (I’ll blog about that very soon). We covered dark matter, and this article, during the workshop.

So the linked article discusses Chandra X-ray observations of “the bullet cluster” which is a collision of two galaxy clusters. The majority of normal, or baryonic, matter as we say, is in the form of very hot gas in clusters. This hot gas emits X-rays that we can see and trace. In the case of the bullet cluster, drag during the collision has impeded the motion of the hot gas. Not the majority of the matter — dark, non-baryonic matter. That has moved on through just as expected without slowing. And we can trace it by the gravitational lensing of background galaxies. Thus the center of mass of the two clusters has become separated from the center of mass of the hot X-ray gas, which constitutes the bulk of the normal matter. You can’t explain away this result by invoking modified Newtonian dynamics, as some try to do for galactic rotation curves and other indirect evidence of dark matter.

So this observation seems like the real deal, the smoking gun if you will, demonstrating the reality of dark matter.

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What is great science fiction?

October 9th, 2005

First a couple of things before I get into the heart of the post.

Today we had our first snow of the season. If you think it’s early, the last three years in Laramie it snowed before the first day of fall. I’m just hoping right now it slacks off and I don’t have to shovel in the morning. It’s a school day.

Tobias Bucknell is posting an update to his survey of novel advances. I’m doing pretty well, all things considered, but you can see I’m not likely a rich man by any means. You don’t write to become rich, and if you do, you’re a fool. Play the lottery instead. It’s easier.

I have an interest in crytozoology and was interested to see this story about a big cat, not supposed to be there, being shot in Australia. Probably a puma or leopard — not as interesting as a thylacine or a yowie , but interesting nonetheless.

Okay, great science fiction. I was recently set off by a movie review, of all things, that Orson Scott Card posted about Serenity. I enjoyed watching Buffy the Vampire Slayer over the years, Angel too, but never got into Joss Whedon’s Firefly. I only watched one I think. It could grow on me I suppose.

First, let me note I didn’t go see Serenity. It’s not really relevant
to what I want to talk about here. I want to talk about Card’s review and some points he makes there.

He talks about what makes great science fiction, and claims it’s good characters in dramatic conflict, or something to that effective. I call bullshit. He’s confusing what makes great fiction with what makes great science fiction, and they’re not the same thing. Great science fiction should have good characters in dramatic conflict, but that is far from sufficient, otherwise we would just call it fiction. Card pays some lip service to “sense of wonder” and points at “Hamlet” with its ghosts, but he seems to be kind of clueless about this topic, at least in this review. Reading the review it’s hard to believe the writer wrote a book called How to Write Science Fiction & Fantasy.

To me, the power of science fiction is in its ability to showcase two things. First, the wonder of the universe as science shows us it really us. Exploring the meaning of quantum mechanics, the behavior of distant star systems, the different forms life and intelligence may take…in short, a fictional approach to exploring reality as we know it through science above and beyond human interactions that Card makes the centerpiece of his vision. Now, I agree with him that great fiction has drama and humanity, and that comes to the second thing I look for in great science fiction: exposing humanity through juxtoposition with ideas and concepts not to be found in everyday life.

Contact with aliens can show us what it means to be human. The ethics of cloning, and individual identity, were explored through science fiction decades before cloning humans was a tangible possibility. Computer intelligence may be coming, too, and what that means to our future, and our self-image, is approachable through science fiction. What does it mean when we can use genetic engineering to change ourselves? You can look at the legacy of humankind with a far future story. You can look at issues of stewardship of our planet. You can do an infinite number of things that let you look at issues that are difficult or impossible to explore in more conventional fiction. Great science fiction does this, and it isn’t great just because of drama and characters.

I think Card’s managed to write great science fiction a few times, but now I wonder if it was an accident. He has counterexamples, too. I mean, no matter how well you do it, how is a science fiction allegory of the founding of the Morman Church ever going to be great science fiction?

Finally, no matter how you like/dislike Card’s work, his take on homosexuals, or what makes great science fiction, you have to trust his judgement. In the last part of his review, he says that if you don’t go see Serenity, you could do worse than staying home and watching reruns of “Full House,” which he makes out to be much superior to “Seinfeld.” Okay, Scott, way to drive your point home.

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Probability Sun

April 2nd, 2005

I finished reading Probability Sun by Nancy Kress on the Hawaii trip, and wanted to plug it here. Probability Sun won the John W. Campbell award for best science fiction novel a few years ago and it was well deserved. Set in the same universe as her award-winning story “The Flowers of Aulit Prison,” Probability Sun features human interactions with two alien species (one rabidly aggresive humans are at war with, another that “shares reality”), and alien technology from a long-gone civilization. Particularly compelling to me was that the conflict was entirely among the humans, all acting toward noble goals individually, but terribly at odds with each other. Probability Sun is the second book of a trilogy, but can be read on it’s own.

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Professors have it easy?

December 13th, 2004

Actually, no we don’t. I sometimes hear people say, or see them write in an online forum, that university professors have it easy. They say that we get a job for life and only have to teach a class or two at a time and, gee, isn’t that easy?

Hardly. I haven’t posted here in about six weeks because my original intent was to make longer, thoughtful posts about things going on in my life and the world I’m interested in. I haven’t had the time. I’m going to try to post interesting, thoughtful things but perhaps always not so long.

After Milehicon, I’ve been observing at WIRO (our local observatory), written a grant proposal to the National Science Foundation, reviewed about 50 proposals to NASA’s Infrared Telescope Facility (IRTF), flown to Orlando for the IRTF review meeting, hit Universal Studios and Epcot Center with my wife for a breif vacation, gotten sick, advised a dozen students about their courses, mentored 3 students in their research, written peer teaching evaluations for three other professors, and, oh yeah, taught a graduate level course on galaxies and cosmology. No one just teaches a grad level course without a lot of preparation. Lots of late nights, but things got done, mostly, at a level I was satisfied with.

Except the blog.

Anyway, in coming weeks, expect to hear about an anthology I’ve proposed to the National Science Foundation to support introductory astronomy, the release of Star Dragon in paperback and as an e-book (available for free from the website here), my plans for teaching astrobiology in the future, and more. My next big event will be the American Astronomical Society meeting in San Diego the second week of January. I’ll be presenting a paper on the astronomy anthology, and Greg Benford will be speaking, both in support of a special session “Astronomy and the Humanities” organized by Andrew Fraknoi. The paperback will be out, too, and I’m trying to line up an event at Mysterious Galaxy.

Finally, I’ll try to post about the novel writing process. I got my revision instructions from my editor at Tor for the new book, and it’s going to be a fair amount of work yet. That’s okay — I expected to do some work, and I trust my editor. The book will improve significantly before it’s published.

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