Planets orbiting two suns are rare. Scientists now understand why. Subtle gravitational forces, amplified by Einstein's relativity, destabilize planetary orbits over eons. This leads to planets being ...

Studying the orbits of thousands of exoplanets shows that large planets tend to have elliptical orbits, while smaller planets tend to have more circular orbits. This split coincides with several other ...

In theory, it could happen – one of the very first solutions to the three-body problem was this scenario. But it is very unlikely to be stable over time. You need the stars to have near equal mass and ...

The classical picture of star and planet formation suggests that a star’s rotational axis and the orbital planes of its planets should be aligned. However, exoplanetary systems have considerable ...

Six planets are set to align on Saturday, creating a planetary parade that will be visible to sky-gazers across the globe.

Planet hunters have grown used to strange worlds, but a handful of discoveries now point to something even more radical: giant planets that loop around their stars on orbits so skewed they almost defy ...