Fascinating, but Useless?

I Don’t Think So

I was browsing around at Borders Books last night, checking out the latest science books. One thing I’ve been noticing over the past few years is that the science sections in bookstores are getting smaller at about the same rate that pseudoscience, religion, and mystery book sections are growing. I don’t know that there’s a strict correlation (and I’m not saying that those three sections are related, so don’t go there), but I note the trend.

Anyway, I ran across this great little book at the counter called the Ultimate Book of Useless Information. I’m a sucker for factoids and little-known data points. So, I bought it and started browsing through it while waiting to pick someone up at the airport.

Since I’m interested in astronomy and space science, and since I’ve been doing a lot of reading on global warming and our atmosphere, a few nuggets caught my eye. First, as it says on page 61, the surface temperature on planet Earth would be 176 Fahrenheit by day and fall to 220 F by night if we didn’t have this atmosphere that sustains us. Also, as it says on page 61, Earth’s atmosphere is proportionally thinner than the skin of an apple.

Interesting facts, these. But useless? I don’t think so. They tell us a lot about our planet in just a few words. Stuff worth knowing. So, I’m not sure why the compiler of these “useless” facts dubs them so, because every fact is a teachable moment, a chance to learn something about the universe. Still, the book makes us think about these facts. It raises questions like “How do they know that?” and “Is that still true?” So, perhaps that’s the authors’ intention. Still, I don’t like seeing facts dismissed as “useless.”

Here’s another one: hot water is heavier than cold water. How do they know that? Can you prove this to yourself? How? A nice little lesson in science and fluid physics, don’t you think?

Here’s another: the human tooth has about 55 miles of canals in it. Ask your dentist about THAT the next time you’re in for a checkup (or, a root canal)!

Here’s a not-so-useless fact: a third of all cancers are Sun-related. That’s news you can use, and proof that much science data IS useful. And I think most people agree with that, once they stop to think about it.

Yet, there are those who reject science for a variety of reasons: ignorance, fear, religious misinterpretation or misunderstanding of the role of science. They may have spurred a bit of head-banging among those of us who see science as a system of knowledge and not the evil, godless practice that a few misguided souls make it out to be. In that case, I offer this last bit that I’ll mention from the book: banging your head against a wall burns 150 calories an hour.

Update: if you get this book, don’t take every “fact” in it that you read as correct. I’ve found a few “facts” that are somewhat sloppily stated, and at least one that’s flat-out wrong and could have been corrected with very simple research. With that caveat, this is still an interesting read, and now can be used as a jumping-off point to sharpen your critical thinking skills by fact-checking the “fact” mongers.

Carnival of Space

Today Fraser Crane over at Universe Today is hosting the third Carnival of Space. Included among the blogged articles is my previous entry (below) about the Dark Matter Ring. Head on over and enjoy Fraser’s commentary and links to other great articles!

I’m Going Down an Invisible Ring of Dark Matter…

With Apologies to the Late Johnny Cash

The galaxy cluster CL 0024+17 (ZwCl 0024+1652) as seen by Hubble Space Telescope's Advanced Camera for Surveys.

A ghostly ring of dark matter in the same galaxy cluster, as inferred by observations of the cluster made by Hubble Space Telescope.

It’s out there. Dark matter. You’ve probably read about it in the papers, or heard scientists talk about it. Nobody’s quite sure exactly what it is, yet. But, we do know it’s out there, distributed in clumps throughout the galaxies in the universe.

Tracking down dark matter, which is one of the great “Holy Grails” of astronomy and astrophysics these days, is no easy matter (so to speak). Dark matter doesn’t give off light, it doesn’t reflect light. It just sits there, making its presence known by the gravitational effect its mass has on light. To find it, astronomers study how the light from more distant galaxies (beyond or “behind” the dark matter clumps) is distorted and smeared into arcs and streaks by the gravity of the dark matter. The smears are produced by a phenomenon called “gravitational lensing.”

One Ring to Rule Them All… and in the Dark Matter Bind Them

Today a team of astronomers announced that they found a RING of dark matter at the heart of a galaxy cluster. An ordinary “visible light” image of the cluster shows galaxies and some smears of light that are distorted images of galaxies behind the cluster. The smears indicate that there’s something in the cluster causing the light from the distant galaxies to bend or distort. That “something” turns out to be a ring of dark matter. Now, if much of the dark matter we’ve “seen” so far in the universe is clumpy, how does a ring of it end up at the heart of a galaxy cluster?

Good question.

According to one of the astronomers, Dr. M. James Jee of Johns Hopkins University in Baltimore, MD, the collision between two galaxy clusters created a much larger cluster, but it also formed a ripple of dark matter separate from the gas and dust components of the cluster that left distinct footprints in the shapes of the background galaxies. “It’s like looking at the pebbles on the bottom of a pond with ripples on the surface,” he said. “The pebbles’ shapes appear to change as the ripples pass over them. So, too, the background galaxies behind the ring show coherent changes in their shapes due to the presence of the dense ring.”

This is the first time such a distinct ring of dark matter has been seen, and at first Jee did not want to believe the ring-like structure was anything but a statistical fluke in the data analysis. But, like any good scientist does, he systematically went through the data, and eventually was convinced it was real.

“I was annoyed when I saw the ring because I thought it was an artifact, which would have implied a flaw in our data reduction,” Jee explained. “I couldn’t believe my result. But the more I tried to remove the ring, the more it showed up. It took more than a year to convince myself that the ring was real. I’ve looked at a number of clusters and I haven’t seen anything like this.”

It’s really quite a cosmic detective story. Dark matter is sort of like the “last frontier” of matter studies in some ways. We know it’s ubiquitous in the universe, and we’re now starting to trace out its distribution, its “shapes” (if you will). There’s more dark matter than “regular” (so-called “baryonic” matter in the universe) and it serves as a sort of gravitational glue to bind galaxies and clusters together.

If you want to read more about this story, and see some very cool animations, go to the Space Telescope Institute website and visit their news center. And stay tuned. I think there’s going to be more news about this “binding force” of dark matter as scientists do more cosmic mapping!