Monday, May 01, 2006

Catch a falling star

"...and the chances of that happening," my friend said on the telephone, "are about the same as a meteorite falling from space and hitting me."

As a former astronomy student, I was quick to assure her that she couldn't possibly get hit by a meteorite. Not unless somebody threw one at her. Or perhaps dropped one on her from a hot-air balloon. But she has no reason to worry about either of those things because meteorites are rare finds, which means people don't tend to use them as slingshot ammo or as ballast for hot-air balloons. Rather, people tend to buy and sell meteorites, often for Serious Money.

Now pay attention, because this is the kind of little-known fact you can trot out whenever you want somebody to think you're clever. Work it into your next conversation and see if you don't get a free beverage out of it, at the very least:

You can't get hit by a meteorite that's falling from space because meteorites do not fall from space. I don't care what your grandfather's cousin Homer saw on that farm in West Virginia back in '49, that cow was not hit by a meteorite.

Is everybody confused? It's really quite simple, so stick with me.

Let's imagine that a hunk of stone with maybe a bit of iron and nickel in it gets knocked loose from an asteroid in a minor collision and begins hurtling toward Earth. That little traveler is called a meteoroid. When the meteoroid enters our atmosphere, the friction is going to heat things up and produce that whole streaky, sparkly, falling-star thing--and at that point our subject will be properly called a meteor. If this meteor doesn't completely vaporize (as most of them do), whatever's left will hit the ground. Now and only now has the little piece of space junk become a meteorite. In other words, a meteor that has hit the ground.

So you see, there's just no way a meteorite could ever fall from space and hit you on the head.

Watch out for those meteors, though.


Mirtika said...

I'm guessing that my head is so close to the ground, or that my head counts as "hitting earth", so yeah, I can get hit by a meteorite. One second after it bops me on the head, it's on the ground. heheh

Actually, there was a time when I had a beat up car causing me all sorts of headaches, when I prayed a meteor the size of two bowling balls, maybe three, would hit my car. This was after seeing an article in ASTRONOMY magazine of a gal who's car got smashed by one, and selling it brought her about 60K or so. (Hey, that buys a car and then some!)

So, if a nice-sized meteor wishes to transform into a meteorite right on my 8 year old Chevy, please, be big enough to bring in at least 50K, all right? :D


Danica/Dream said...

Huh. The things you learn from a blog.

So do you know anything about the SETI projects out there? I'm doing a little research. :)

Brenda Coulter said...

Mir, here's an interesting link. And here's another one, with pictures.

Dream, I used to study with someone who was very involved with SETI, but that was years ago, and I was interested in optical rather than radio astronomy. But you should be able to find plenty of info if you Google "SETI Phoenix".

Anonymous said...

What a little gem of a piece. I put something in my Ramble last week about NASA's new announcement that we wouldn't be hit (by whatever)... now I can brush up on the terminology. Thanks!

Mirtika said...

Thanks for the links, Brenda.

I actually saw the Willamette up close. I was transfixed. To a space-obsessed kid, it was just one of those amazing moments of the ineffable. I don't know why. I don't care. It made me feel wonder. If I could have licked it, I think I would have. :D