
How an Amateur Meteorite Hunter Tracked Down a Fireball - mhb
http://www.nytimes.com/2016/03/11/science/how-an-amateur-meteorite-hunter-tracked-down-a-fireball.html
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nkurz
1) I'm surprised that meteorites would end up on the surface rather than
embedded in the ground. I'd have thought that a hunk of metal or stone falling
from the sky would penetrate rather than bounce. Is it a matter of the angle
that it comes in at? Is the terminal velocity just that slow? Or do most of
them bury themselves and it is only the ones that remain on the surface that
are found?

2) There was an interesting story that came out a couple months ago about a
new "trove" of meteorites being found in Antarctica. While quite a few have
been found on the surface, there was a recent realization that more should
have melted their way in after being heated by the sun:
[http://www.universetoday.com/127492/does-antarctica-have-
a-h...](http://www.universetoday.com/127492/does-antarctica-have-a-hidden-
layer-of-meteorites-below-its-surface/)

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xyzzyz
It's actually pretty interesting that the impact speed is not that crucial
when it comes to how deep the projectile is embedded. Isaac Newton was the
first to explain it and to approximate how deep a projectile can go -- it
boils down to the density ratio of the impactor and the target material.
Additionally, penetrating the atmosphere itself can be thought of as
equivalent to penetrating 10 meters of water, so the projectile already loses
a lot of energy to push through it.

See
[https://en.wikipedia.org/wiki/Impact_depth](https://en.wikipedia.org/wiki/Impact_depth)
for more explanation.

