Download Space Rocks - American Geosciences Institute

Space Rocks
Impacts of our smallest neighbors
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Asteroid
Asteroid
Belt
Belt
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Primitive Solar System
The four inner planets formed,
but Jupiter’s huge gravity caused
chaos in the region past Mars.
No big planet ever formed there
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Craters in the Inner
Solar System
Mercury
Mars’s Southern Highlands
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Impacts
on Moons
Mars’s tiny moon Phobos
Mimas, a moon of Saturn
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Lunar Cratering
Our Moon
shows a
history of
impacts
Most of these
occurred long
ago…
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The Asteroid Belt is Sparse
On average, there are
more than 1 million km
between asteroids
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Dynamic
Collisions
Do
Occur
And the effects
are seen
throughout the
Solar System
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Jupiter Shows Recent Impacts
The world watched as a
comet collided with
Jupiter in 1994
Possibly not as rare as we
thought. Other collisions
have occurred since, like
this one in 2009
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More than 170
Impact Craters on Earth
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Earth Erases
History of Impacts
Barringer Crater, Arizona
Roter Kamm, Namibia
Wolf Creek, Australia
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Chicxulub and the Dinosaurs
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Recent Earth Impacts
2008 TC3- first celestial object
tracked by astronomers before
entering Earth’s atmosphere
Tunguska in Russia 1909
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Meteorites
Chunks of asteroids sometimes make it through
the atmosphere to the ground
These are time capsules telling us about how
matter came together in the early Solar System
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Future Impacts
• Meteoroids smaller than a house
will explode in our atmosphere
5-10 meter objects hit about once a year
• Larger objects are rare but devastating
We don’t know when the
next big impact will happen,
but it will eventually
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Can we Stop an Impact?
Our best chance of avoiding
an impact is having
advance notice of a threat
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NASA’s
WISE Mission
Using Infrared
technology to see
dark asteroids

WISE finds asteroids - including
some seen for the first time
 100,000s of Main Belt Asteroids
 100s of Near-Earth Objects
(NEOs)
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The Challenge Could be Ours
If we do find an asteroid headed for Earth…
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