The number of planets that orbit the sun depends on what you mean by “planet,” and that’s not so easy to define ...

Mercury takes only 88 Earth days to orbit the sun.

However, this year a powerful new telescope is coming online that could prove once and for all that there really is a ninth planet in our Solar System. The same year that Pluto was ignominiously ...

The solar system consists of 8 planets, including Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. Each planet has its own unique characteristics, such as size, composition ...

For much of January and February, you have the chance to see six planets in our solar system after dark, although two — Uranus and Neptune — will be hard to see without a telescope or high-powered ...

upending previous theories of how planets are formed and structured and giving scientists a tempting window into the otherworldly diversity of planets beyond our Solar System. Enaiposha, discovered in ...

A very rare treat is about to grace Earth's night skies.