October 25, 2007 12:36

Black Holes Galore

The circled galaxies all contain giant black holes. / NASA/JPL-Caltech/ Commissariat a l'Energie Atomique

Theory says that most of the galaxies formed shortly after the Big Bang should have giant black holes lurking in their cores--but until now, astronomers haven't seen much evidence. You can't see a black hole directly, but when gas falls into its voraciously powerful gravitational field, the gas heats up and glows brilliantly. Except that so far, it hasn't, as far as observers could tell.

But it turns out that at least some black holes have been blazing all along; they were just shrouded by dust. It took the infrared-sensitive Spitzer Space Telescope to peer through the dust, and the Chandra X-Ray Observatory (also in space) to find the telltale X-rays that betray the presence of super-hot gas that surrounds the black holes.

That's one mystery down. Luckily for science reporters, there are always more.

Sphere Related Blogs & Articles

|

October 1, 2007 5:00

Flash: Saber-Toothed Tiger Was Really Dangerous

When I was a kid, toy dinosaur sets usually came with a little toy saber-toothed tiger, formally known as Smilodon. It wasn't because the toymakers were Creationists who thought every animal that ever lived was on the Earth at one time, but rather because the saber-tooth had the same appeal as the dinosaurs did: it was exotic-looking, really scary and safely extinct (although, unlike the dinosaurs, it did prowl the Earth when our human ancestors were around, finally going extinct only about 10,000 years ago.

Actually, the saber-tooth wasn't a tiger at all, which is why paleontologists call them saber-toothed cats instead (or some variation). Now Australian researchers have made a new discovery about the nightmarish-looking beasts, being reported today in Proceedings of the National Academy of Sciences. What interests me, though, isn't the discovery itself so much as the way they're trying to sell it to the media. The headline on the press release reads: "Scientists say sabercat bit like a pussycat."

If you're like me, you probably assume this means they're saying the cats weren't all that dangerous after all. If so, we're both wrong. You don't have to read very far into to the release before you realize that all they're talking about is the bite. According to a computer-based analytical technique borrowed from engineering, called finite element analysis, the saber-tooth's bite was only a third as powerful as a modern lion's. "It bit," one of the scientists says in the press release, "like a moggy."

Leaving aside the fact that I never heard the term "moggy" before this minute, the release goes on to admit that the saber-tooth cat could still rip you into small pieces in seconds. It would just bite you less hard than a lion while doing so (probably more like a pit bull—what a relief!).

It actually is interesting science, if you're following what they call the "150-year-old debate" about how hard a saber-tooth could bite. And it shows how a technique invented to study the structural strength of manufactured items can be borrowed by biologists.

But that headline may be just a tiny bit too sensational, don't you think?

Sphere Related Blogs & Articles

|