Planet Floats!

Some planets so are light that they could float in a giant tub of water. A recent discovery by Smithsonian astronomers has resulted in a very unusual find. Known as HAT-P-1 a new planet that is about 1.38 the size of Jupiter has a mass that is less than half that of Jupiter.

Astronomers found the planet by using a process in which they observe a distant star and measure its light. At regular intervals, a large planet will obstruct the face of the star directed at earth and lower its brightness as it passes by in its orbit around the star. This particular planet (HAT-P-1) goes around its sun every four and one-half days. Amazingly the planet is only one-twentieth the distance to its star as earth is to our own sun. This planet is light and it's fast.

According to scientists this planet has a density that is lighter than a giant ball of cork, about ¼ that of water. It is about 24 percent larger than theories expect a planet to be for its mass.

In our own solar system, Saturn has similar properties. Saturn is almost as large as Jupiter yet it has a much lower density. Saturn can also float in water. The ringed planet also spins very fast. Combine a fast rotation and a low density and you get an unusual property. Saturn is elongated in shape. It is flattened at the equator. That makes for a very interesting planet, what with its rings, its many moons, its density and its shape.

Because of the newly discovered, "lighter," planets, scientists will have to rethink current theories of planet formation.