EOS - The folks next door can have a big impact on the livability of a neighborhood. If they’re loud, pushy, and obnoxious, they can force you out of even the most comfortable of homes.
That truism applies to planets as well as people. The wrong kind of neighbor can kick an Earth-like planet out of its star’s comfort zone or out of the system entirely, or even prevent it from forming in the first place.
Although giant planets similar to Jupiter can help protect other planets by kicking away potential comets or asteroids, a pair of recent studies supports the idea that other giant planets can make it almost impossible for Earth-like worlds to remain in stable orbits inside a star’s habitable zone—the region where temperatures are the most conducive to liquid surface water. Simulations of two planetary systems show that known giant planets in or near the habitable zone would quickly boot out Earth mass planets or nudge them into orbits that would create dramatic swings in climate, lessening their chances of hosting life.
“Hundreds of factors govern the habitability of planetary systems,” said Stephen Kane, a professor of Earth and planetary sciences at the University of California, Riverside and author of both papers. “How planets interact gravitationally is one of the most important.”