Hi Bob and thanks for the links. It is interesting that 40% of the Top 5 cosmic myths have to do with meteors/meteorites.
With all the other mysterious objects in the cosmos, I wonder why there are not more exciting things than meteorites to misunderstand. I guess that is a good thing given our fascination with them. Cheers, Martin On 12/13/02 2:22 PM, "Robert Verish" <[EMAIL PROTECTED]> wrote: > From a Space.com article earlier this year: > > <http://www.space.com/scienceastronomy/top5_myths_020903-4.html> > > Top 5 Cosmic Myths (cont.) > > Myth #4 - Meteors are heated by friction as they pass > through the atmosphere . . . > > > This one makes sense, which is why it's so pernicious. > But it's STILL WRONG. > > Meteoroids are tiny bits of dust, rock, ice or metal > that have the unfortunate luck of having their orbits > intersect the Earth's. When they pass through our > atmosphere, they are heated so ferociously that they > glow (and at this point are called meteors), and are > visible for hundreds of miles. > > However, it is not friction that heats them. Think of > it this way: a space shuttle's tiles are extremely > delicate; they crumble easily in your hand. If they > were heated by friction as the shuttle de-orbits and > enters the atmosphere at Mach 25, the tiles would > disintegrate. That's not a very good design > characteristic. > > In reality, it isn't friction, but ram pressure that > heats the meteoroid. When a gas is compressed it gets > hot, like when a bicycle pump is vigorously used to > inflate a tire. A meteoroid, moving at 33,500 mph (15 > kilometers a second) or more compresses the air in > front of it violently. The air itself gets very hot, > which is what heats the meteoroid. That's the fact, > not friction. > > See Next Message for Myth #5: More on this Hot Topic > > > > __________________________________________________ > Do you Yahoo!? > New DSL Internet Access from SBC & Yahoo! > http://sbc.yahoo.com > > ______________________________________________ > Meteorite-list mailing list > [EMAIL PROTECTED] > http://www.pairlist.net/mailman/listinfo/meteorite-list ______________________________________________ Meteorite-list mailing list [EMAIL PROTECTED] http://www.pairlist.net/mailman/listinfo/meteorite-list
