Tilted Forum Project Discussion Community - View Single Post - How many planets are in our solar system?

proplyd · 07-23-2008, 12:09 PM

It has been a while since anyone posted here. It has been since before the International Astronomy Union demoted Pluto to a dwarf planet. If this one goes though, it will be my first.

They unintentionally demoted another planet when they got Pluto, the smallest of the traditional nine planets. They also demoted Jupiter, the largest of them.

The new definition of a planet requires that it orbit the Sun. Jupiter does not, technically. The center of mass between Jupiter and the Sun, their barycenter, lies a whisker outside the surface of the Sun. Technically, Jupiter and the Sun orbit each other. Jupiter does not orbit the Sun, and therefore is not a planet.

07-23-2008, 12:09 PM	#13 (permalink)
proplyd Upright Location: Royersford, PA, USA	Jupiter is not a Planet It has been a while since anyone posted here. It has been since before the International Astronomy Union demoted Pluto to a dwarf planet. If this one goes though, it will be my first. They unintentionally demoted another planet when they got Pluto, the smallest of the traditional nine planets. They also demoted Jupiter, the largest of them. The new definition of a planet requires that it orbit the Sun. Jupiter does not, technically. The center of mass between Jupiter and the Sun, their barycenter, lies a whisker outside the surface of the Sun. Technically, Jupiter and the Sun orbit each other. Jupiter does not orbit the Sun, and therefore is not a planet. __________________ There are 10 kinds of people in the world. Those who understand binary, and those who do not.