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Science plausibility question - The Phantom Librarian
Spewing out too many words since November 2003
Science plausibility question
This doesn't strike me as plausible, but before I put it in a book review, I'd like to get second opinions.

The scenario is this:
During a meteor shower, an iron asteroid comes through the roof of a boy's home, goes through his mattress, and stops at the floor. On landing, it is the size of a baked potato.

It seems to me that a wood-frame house and a bedroom mattress wouldn't be enough to stop something of that size hurtling down at around 17k per second (the average speed of an asteroid hit). It wouldn't leave a hole in the world, but you're not going to stuff the hole in the mattress with a couple of old t-shirts and sleep in that bedroom.

Or, I could be totally wrong. Oh, physics-astronomy folk... if the remainder of an iron asteroid at impact is the size of a baked potato, what's the damage?

ETA: Really fun site I found while trying to track down an answer. Unfortunately, it doesn't give the size of the asteroid after burn-through, just before (I think; it wasn't clear).
16 comments or Leave a comment
rabidsamfan From: rabidsamfan Date: June 15th, 2010 02:00 am (UTC) (Link)
Of course, my question is, how much stuff in the attic slowed it down?
fernwithy From: fernwithy Date: June 15th, 2010 02:06 am (UTC) (Link)
That's a good point. I don't know the impact of the old Christmas decorations variable. ;p
From: iamweebles Date: June 15th, 2010 02:22 am (UTC) (Link)
Interestingly enough, here's a story about a fist-sized meteor that crashed into a doctor's office - you can see the damage it left.


It does look like the impact, while intense, is very localized, and yes, I think it wouldn't make a big hole, but it would go deep.
fernwithy From: fernwithy Date: June 15th, 2010 02:38 am (UTC) (Link)
Yeah, and it looked like it did some damage to the concrete floor--a wooden floor wouldn't stand much chance.
rabidsamfan From: rabidsamfan Date: June 15th, 2010 03:12 am (UTC) (Link)
That site is fun. At first I thought it was like the set at the Museum of Science and Nature in Denver (where you can destroy the planet if you like) but there was no animation....

Still, the data's pretty neat.
(Deleted comment)
fernwithy From: fernwithy Date: June 15th, 2010 07:10 am (UTC) (Link)
All right--bookbusters episode!
From: (Anonymous) Date: June 15th, 2010 08:16 am (UTC) (Link)
Wouldn't the asteroid also be white-hot, due to the friction generated as it falls through the atmosphere? The mattress would catch fire, in fact they'd be lucky if the whole house didn't catch fire. If the house is occupied at the time it would probably be easy enough to put the fire out, but then you've got a singed, soaking wet mattress with a hole in it......
mcgonagalls_cat From: mcgonagalls_cat Date: June 15th, 2010 08:48 am (UTC) (Link)
I would think it would be so hot that it would catch everything on fire, too.

And, the size of a potato would seem to almost make an explosive sort of situation. I would think that it would be much smaller.
yohumblenarr8or From: yohumblenarr8or Date: June 15th, 2010 09:33 am (UTC) (Link)


You're right, it does sound implausible. I kind of imagine the force of the hit would at least knock you out of bed if you were sleeping at the time. It sounds almost painful. But maybe the roof, ceiling and subsequent floors would slow it down before it reached the mattress and slowed enough to stop? I'll say stranger things have happened. Although the fact that is baked-potato size is what's throwing me. If it were smaller, it'd be easier to believe.
sgt_majorette From: sgt_majorette Date: June 15th, 2010 11:03 am (UTC) (Link)
Okay, English, French, German, Russian -- and Welsh???
satakieli From: satakieli Date: June 15th, 2010 11:19 am (UTC) (Link)
So the damage would be directly proportional to the kinetic energy the meteorite has when it lands. A remnant the size of a baked potato will have reached terminal velocity by the time it hits. The energy is equal to the mass (perhaps about a kilogram for a dense rock the size of a baked potato?) times the square of the velocity. I've been surfing around to see if I can find the terminal velocity of a 1 kg rock, but no luck.

If you find that, the classic way to scale explosions is to compare to the mass of TNT that would produce the same effect.

Hm. I meant to help, but I think I may just have confused the issue more. I wish I were more comfortable with drag; I might be able to give you an estimate on the terminal velocity. Sadly, I am not.
From: tree_and_leaf Date: June 15th, 2010 12:52 pm (UTC) (Link)
Could he be sleeping on the ground floor?
fernwithy From: fernwithy Date: June 15th, 2010 04:11 pm (UTC) (Link)
He was outside; the bedroom was on the second floor.
From: (Anonymous) Date: June 15th, 2010 02:24 pm (UTC) (Link)
I found several online references to a meteorite that actually did land in a bedroom in 1954. According to some other sites, smaller meteorites (ones not causing extinction of dinosaurs and all that) lose momentum from air friction, etc. ("etc" meaning I just skimmed the explanation and took their word for it).

Anyhow, this was the most detailed one I came across about the 1954 one. Although it's a dot-edu, the internet being the internet, you might want further verification.



The chances of a meteorite hitting your house are very small, but it does sometimes happen.

In the last 200 years, 145 meteorites have fallen in the United States. In 2003, two meteorites fell in U.S. cities. On March 26, 2003, just before midnight, hundreds of fragments of a large meteorite fell in the Park Forest area of Chicago. Several fell through roofs of houses, and one punched a hole in the roof of the fire station. One large piece, weighing about 2.5 kg, crashed into a bedroom and bounced off the window sill, narrowly missing a boy who was asleep in his bed. On September 23, 2003, a 20 kg stone meteorite tore straight through a two-storey house in New Orleans and came to rest in the basement. Since then, there has only been one witnessed U.S. fall: a small meteorite that fell in Orlando in 2004.

Even more rarely, meteorites can also hit people. The most famous recent event was in Sylacuaga, Alabama in 1954, when a 4 kg stone hit Mrs. Hulitt Hodges who was asleep on a couch. Mrs. Hodges suffered a bruised hip and lived to tell the tale!
From: (Anonymous) Date: June 15th, 2010 02:27 pm (UTC) (Link)
Oops, I said bedroom when it hit her on the couch. So, that's how awake I am in the morning when I type this stuff. Take that into consideration when evaulating the research.

From: (Anonymous) Date: June 17th, 2010 12:09 am (UTC) (Link)

You're right, that IS a fun site, I destroyed Cardiff! EOM

You're right, that IS a fun site, I destroyed Cardiff! EOM
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