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Space Station Info >> Meteors
Meteors
Most of us probably have seen
meteors or shooting stars. A meteor is the flash
of light that we see in the night sky caused by
the friction of a meteoroid passing through our
atmosphere. A meteoroid is an interplanetary chunk
of matter smaller than a kilometer and frequently
millimeters in size. (Note that the term "meteor"
refers to the flash of light caused by the meteoroid,
not the meteoroid itself.) Most meteoroids that
enter the Earth's atmosphere are so small that
they vaporize completely and never reach the planet's
surface. If any part of a meteoroid survives the
fall through the atmosphere and lands on Earth,
it is called a meteorite. Although the vast majority
of meteorites are very small, their size can range
from about a fraction of a gram (the size of a
pebble) to 100 kilograms or more (the size of
a huge, Earth-destroying boulder).
Asteroids are generally larger
chunks of rock that come from the asteroid
belt situated between the orbits of Mars
and Jupiter. Comets are asteroid-like objects
enclosed with ice, methane, ammonia, and
other compounds that form a coma and sometimes
a visible tail whenever they orbit close
to the Sun. As a comet rides through the
solar system, it leaves little particles
in its wake. If the Earth's orbit intersects
this "wake" of particles, we see
a meteor shower as the particles rain down
through Earth's atmosphere. |
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Also see
vRegions
Where The Comets Are Found
vOrbits
Of Comets
vAsteroids
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