More Moon and Jupiter
The 800-pound gorilla of the solar system huddles close to the Moon before dawn tomorrow. It looks like a brilliant star a little to the Moon's lower right.
Jupiter is the solar system's largest planet. It's more massive than all the other planets and moons combined.
Because of its great mass, Jupiter has a strong gravitational field. And that gives it a strong influence over the rest of the solar system.
As the planets were taking shape, Jupiter hurled many of the building blocks for planets completely out of the solar system. That pushed Jupiter itself a little closer to the Sun.
Jupiter also swept up many of those building blocks. That not only made Jupiter itself bigger, it also protected Earth and the other planets from impacts by many of the giant balls of ice and rock. In fact, Jupiter still performs that role today. Over the last couple of decades, it's pulled apart at least a couple of comets and been hit by their remains.
And Jupiter's gravity kept a belt of debris that was closer to the Sun from coalescing to form another planet. Today, that debris forms the asteroid belt -- a broad ring between Jupiter and Mars.
Jupiter's gravity also herded a few asteroids into two clumps -- one that leads Jupiter around the Sun, and another that follows.
So as you watch Jupiter tomorrow, keep in mind that it's the big guy on the block -- a world that helps keep the rest of the solar system in line.
Script by Damond Benningfield, Copyright 2011
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