Travel through time to witness some of the most remarkable episodes in our solar system's history, uncovering its ancient ...

The Milky Way and Andromeda galaxies are predicted to collide and merge between 3.9 and 5.6 billion years from now, based on observed relative motion. The merger process will involve multiple ...

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 ...