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 ...

Lucas Brefka receives funding from a NASA Exoplanet Research Program grant. Christopher Palma does not work for, consult, own shares in or receive funding from any company or organization that would ...

A small team led by Sihao Cheng, Martin A. and Helen Chooljian Member in the Institute for Advanced Study's School of Natural Sciences, has discovered an extraordinary trans-Neptunian object (TNO), ...

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Is there a massive undiscovered planet on the outer reaches of the solar system? The idea has been around since before the discovery of Pluto in the 1930s. Labeled as planet X, prominent astronomers ...