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Transcript
Minor Members
Things that didn’t make
up the sun, planets or
moons.
Asteroids
• Rocky objects usually larger
than a mile across.
• Most are found in the Asteroid
Belt between Mars and Jupiter
• Earth has been hit by asteroids
in the past.
Comets
• Are mostly made of ice.
• Orbit the sun.
• Their return can be predicted.
• Their tail shows the direction of
the sun, not which way they are
headed.
Meteoroids
• Small (less than 1 mile) rocks in
space.
• When they enter a planets
atmosphere they are meteors.
• When they strike the ground, they
are meteorites.
We Have Been Hit
• The moon shows it’s record of
impacts because it has no erosion.
• Earth shows only recent signs of
impact.
• One major theory says that we
were hit 65 MYA and this killed
the dinosaurs.
Iridium
• Iridium is very rare here on
Earth but plentiful in
asteroids.
• A layer of Iridium is found at
the K-T boundary (65 MYA)
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