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Originally Posted by UnderseaLcpl
Wow, I had no idea that air resistance had such an effect on objects entering the atmosphere. I knew it was significant, but not to such a degree.
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It's no so surprising when you think of those intense re-entry
temperatures objects entering the atmosphere build up. All that
heat comes from the drag causing them to expel their kinetic energy.
The air gets highly pressurized in front of the object and becomes a
dense, hot soup. Not easy to push through.
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Okay, one more question, if you'll bear with me; The Tunguska blast was supposedly caused by a meteorite. How fast must that rock have been traveling to instantly explosively vaporize its entire mass, assuming it was made of the usual combination of porous but high-density rock and iron?
You don't have to do any calculations or anything, I'm just wondering if you know off the top of your head.
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Haha! I'm no physicist. A bit of googleing tells me that most
extraterrestrial objects enter the atmosphere at 5 - 20 km/s.
I would
guess that objects that meet the atmosphere at an acute
angle would be more likely to explode and that ice would play a big
factor, but I really have no idea.