Astronomers propose a new hypothetical planet, Planet Y, beyond Neptune, based on observed orbital anomalies in the Kuiper ...

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

NPR's Ari Shapiro talks with astronomer David Jewitt about what we can learn from the third interstellar object to have entered our solar system, a comet-like object known as 3I/ATLAS.

The new image, which shows Earth along with an even smaller point of light coming from the moon, harkens back to Carl Sagan's ...