Astronomers have found a compact solar system whose planets line up in a way that, according to current models, should not be possible. Around the small star LHS 1903, a dense rocky world orbits on ...

Deep within the Kuiper belt, some small worlds look like they were assembled from two mismatched snowballs pressed together.

Astronomers have found a rocky planet where it should not exist, orbiting far from a cool red star. Could this strange ...

Since the 1990s, scientists have discovered approximately 6,100 planets outside our solar system, called exoplanets.

Illustration comparing the planets of the Solar System and the Sun on the same scale. The planets are shown to scale relative to each other but their distances are not. From left to right the bodies ...