Planet V

Planet V is a hypothetical fifth planet hypothesized by NASA scientists John Chambers and Jack Lissauer to have once existed between Mars and the asteroid belt, based on computer simulations. Chambers and Lissauer presented this idea during the 33rd Lunar and Planetary Science Conference, held from March 11 through 15, 2002.

Chambers and Lissauer proposed that a previously unknown terrestrial planet once existed in an eccentric and unstable orbit around the Sun, at least 4 Ga (four thousand million years) ago. They connect this planet, which they name Planet V, and its disappearance with the Late Heavy Bombardment episode of the Hadean era. [cite web|title=Long-Destroyed Fifth Planet May Have Caused Lunar Cataclysm |work= Space.com |url=http://www.space.com/scienceastronomy/solarsystem/fifth_planet_020318.html| accessdate=2006-11-09 ] [cite web|title=A NEW DYNAMICAL MODEL FOR THE LUNAR LATE HEAVY BOMBARDMENT |work= Chambers and Lissauer, NASA Ames|url=http://www.lpi.usra.edu/meetings/lpsc2002/pdf/1093.pdf| accessdate=2006-11-09 ]

"The extra planet formed on a low-eccentricity orbit that was long-lived, but unstable," Chambers reported. About 3.9 billion years ago, Planet V was perturbed by gravitational interactions with the other inner planets. It was tossed onto a highly eccentric orbit that crossed the inner asteroid belt, a reservoir of material much larger then than it is today. It spun through the inner belt of asteroids, causing them to fly into Mars-crossing orbits. This temporarily enhanced the population of bodies on Earth-crossing orbits, and also increased the lunar impact rate.

According to Chambers, Planet V is thought to have been destroyed when it plunged into the Sun.

ee also

* Phaeton (hypothetical planet)

References