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Norwegian skydiver nearly struck by meteorite

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Re: Norwegian skydiver nearly struck by meteorite

#41

Seems strange that the other diver is following the same path as the meteorite and passes by just a few seconds later. Could he have dropped it and it accelerated to a speed faster than he was travelling?

ie, thrown it? That does seem far more likely than it being from space.

Re: Norwegian skydiver nearly struck by meteorite

#42
post #31

JFYI To be hit by a meteorite you would either need to be close to the Earth's surface or for somebody strong to throw it. Technically it is not a meteorite until it impacts with the Earth's surface, therefore this object may actually be a meteoroid.

> Technically it is not a meteorite until it impacts with the Earth's surface, therefore this object may actually be a meteoroid. Not quite. Before entering Earth's atmosphere, it's a meteoroid. While passing through the atmosphere, it's a meteor. After landing, it's a meteorite. http://www.livescience.com/27183-asteroid-meteorite-meteor-m...

Meteor is a description of the burning in the atmosphere not the object itself, which is still a meteoroid.

Re: Norwegian skydiver nearly struck by meteorite

#44
post #31

Earlier quoted context omitted.

> Technically it is not a meteorite until it impacts with the Earth's surface, therefore this object may actually be a meteoroid. Not quite. Before entering Earth's atmosphere, it's a meteoroid. While passing through the atmosphere, it's a meteor. After landing, it's a meteorite. http://www.livescience.com/27183-asteroid-meteorite-meteor-m...

Meteor is a description of the burning in the atmosphere not the object itself, which is still a meteoroid.

> Meteor is a description of the burning in the atmosphere not the object itself ...

Yes, fair enough. Unless the object is consumed in the process of generating the visible presentation (often true), which makes it a meteor -- or perhaps I should say "turns it into a meteor".

Re: Norwegian skydiver nearly struck by meteorite

#46
A related question: what's the probability of an aircraft being struck by a meteor. Seems this question was asked in the wake of the Air France flight 447 disappearance (since resolved as pitot tube freezing combined with pilot error and control feedback failures of the Airbus design).

But still, the odds of a strike on _an_ aircraft over the next 20 years are about 4%:

http://blog.revolutionanalytics.com/2009/06/how-much-of-a-th...

at any given time, airliners cover 2 billionths of the Earth's surface. There are 125 meteors an hour, each with probability 2x10-9 of striking some airplane. In 20 years, that's about 22 million independent possible impact events. The chance that every one of those meteors misses every airplane is: ppois(0,2e-922e6)*

(Using R).

So the odds of an asteroid flying past a skydiver aren't as infinitesimal as one might otherwise think.

It also makes one wonder at the possibility of space-junk collisions being the cause of past aviation accidents. There's little enough evidence this would leave, particularly for a flight which disappeared entirely without a trace, or whose wreckage was only found much later.

Re: Norwegian skydiver nearly struck by meteorite

#47
I'm... skeptical. If you look at the frames of the meteorite falling, it looks like each frame has the fragment at about 3 feet from its last position. If that's a 60fps camera (I think it is?), that's 180 f/s speed or 122mph. That seems really slow for a rock flying into the atmosphere from space, and far slower than a rock would have to be going for it to "cut him in half."

My guess: a rock that fell off the undercarriage panel of an airliner, and was carried by strong winds. Or a particularly slow meteorite.

Re: Norwegian skydiver nearly struck by meteorite

#48
post #41

Seems strange that the other diver is following the same path as the meteorite and passes by just a few seconds later. Could he have dropped it and it accelerated to a speed faster than he was travelling?

ie, thrown it? That does seem far more likely than it being from space.

If he threw a rock of that size at his buddy ... what a jerk

Re: Norwegian skydiver nearly struck by meteorite

#49

Isn't it more likely that the rock fell out of their plane?

Given its a wingsuit jump he's likely miles from where they exited the plane. The rock would have a more straight down trajectory as well. You can tell the forward speed when the other jumper comes by.
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