Astronomers studying the Kuiper Belt have detected a strange distortion that could point to an unknown planet lurking far beyond Neptune.

TEMPE, Ariz. a Quick: What’s the order of the planets in the solar system? Need a little help? Maybe the following mnemonic rings a bell: “My Very Educated Mother Just Served Up Nine Pizzas.” It’s ...

Theorbits of Jupiter, Saturn, Uranus and Neptune may have been altered by the fly-by of an enormous object from deep space, billions of years ago. According to a pre-print research paper, which is yet ...

The Sun is an incandescent but benevolent dictator. For billions of years, it’s kept our star system well organized through the influence of its powerful gravity. All the planets revolve around it on ...

This article was originally featured on The Conversation. Are planets in the solar system that are closer to the Sun older than the ones further away? – Gavriel, age 10, Paducah, Kentucky A cloud of ...

An artist's impression shows the "inside out" planetary system around the star LHS 1903. - ESA An exoplanetary system about 116 light-years from Earth could flip the script on how planets form, ...

They should all be visible in the same part of the sky shortly after sunset, creating what is often called a planetary parade. Mercury, Venus, Saturn and Jupiter should be visible to the naked eye but ...