Mercury is the smallest planet in our solar system. Explore its size, extreme temperatures, core structure, and comparison with Pluto.

A newly studied solar system breaks the usual planet pattern, raising fresh questions about how rocky and gas planets form.

Jupiter is the largest planet in our Solar System and the fifth planet from the Sun. It is a massive gas giant made mostly of ...

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 ...

Astronomers have uncovered a massive new trans-Neptunian object, 2017 OF201, lurking at the edge of our solar system. With an orbit stretching 25,000 years and a size that may qualify it as a dwarf ...