A new study suggests yet another theory for a possible extra planet in our solar system, likely of a size between Mercury and ...

This video explains why planets in our solar system orbit in nearly the same plane, tracing their origins back to a rotating ...

Pluto's unusual eccentricity and tilt is likely due to its interactions with neighboring Neptune and other giant planets, ...

A new Tatooine-like planet outside the solar system may orbit two failed stars, scientists reported Wednesday. Located about 120 light years away, the exoplanet appears to take an unusual path around ...