IMPACT simulates a comet breaking up then impacting a planet.

When Shoemaker-Levy hit Jupiter, I became interested in two problems. Firstly why were all the chunks in a line like a railway train and what was the best way to deflect a comet on a collision sourse with Earth?



Why are the chunks in a line?

Turn off the planet.

Hit the "bomb" button. The comet breaks up.

Watch the close-up window. Look how the chunks line up. The more often the orbit the sun, the more of a line they make.

Does it matter at what point in the orbit, the comet breaks up?

How to deflect a comet?

Turn on the planet.

If you do nothing, the comet hits the Earth.

Hit one of the "deflect" buttons. Does the comet miss?

What's the minimum number of hits you need for the comet to miss? What if you had only got a limited number of missiles of limited strength?

Does it matter when in its orbit you hit the comet?

Is it better to deflect the comet sideways, speed it up or slow it down?

How to break-up an asteroid?

Where is the best place to put a bomb on an asteroid to deflect it? Does it matter what the asteroid is made of? If you deflect it, it won't hit the Earth. If you break into small pieces, they will burn up in the atmosphere.

These pages show simulations of different explosions.


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