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Space Rocks. Impacts of our smallest neighbors. Asteroid Belt. Asteroid Belt. 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. Craters in the Inner Solar System.
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Space Rocks Impacts of our smallest neighbors
Asteroid Belt Asteroid Belt
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
Craters in the Inner Solar System Mars’s Southern Highlands Mercury
Impacts on Moons Mars’s tiny moon Phobos Mimas, a moon of Saturn
Lunar Cratering Our Moon shows a history of impacts Most of these occurred long ago…
The Asteroid Belt is Sparse On average, there are more than 1 million km between asteroids
DynamicCollisionsDo OccurAnd the effects are seen throughout the Solar System
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
Earth Erases History of Impacts Barringer Crater, Arizona Roter Kamm, Namibia Wolf Creek, Australia
Recent Earth Impacts 2008 TC3- first celestial object tracked by astronomers before entering Earth’s atmosphere Tunguska in Russia 1909
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
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
Can we Stop an Impact? Our best chance of avoiding an impact is having advance notice of a threat
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)
The Challenge Could be Ours If we do find an asteroid headed for Earth…