This article was originally published at The Conversation. The publication contributed the article to Space.com's Expert Voices: Op-Ed & Insights. The size of the solar system is defined by the volume ...

Astronomers have found likely evidence of an Earth-like planet in the Solar System that may be circling the Sun in an orbit beyond Neptune. Physicists, including those from the National Astronomical ...

Gareth Dorrian does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond ...