Habitable planets may be lurking in the wake of Jupiter-like planets as they orbit distant stars, according to simulations led by the Uppsala Astronomical Observatory in Sweden.

Objects born in Jupiter’s wake may have merged to form the planet Saturn, which was then nudged into its current position by the gravity of other planets, the team says (www.arxiv.org/abs/0810.3192).

Outside our solar system, some gas giant planets have been detected in the habitable zone of their stars, and could be found by the small gravitational tugs they exert on their larger, known siblings, according to MIT scientists.