Mathematicians calculated where the planet might be based on its effects on Uranus, and astronomers searched for less than an ...

Astronomer and Pluto mission leader S. Alan Stern explores how the field has transformed during his decades-long career.

Astronomers have discovered the raw ingredients of planets orbiting two infant stars, offering a glimpse into how new worlds ...

Astronomers have discovered what they think may be another moon orbiting a distant dwarf planet called Quaoar. This small, ...

This discovery was made by two of NASA’s most celebrated telescopes. This illustration provided by Dan Durda shows the exoplanet Kepler-1625b with a hypothesized moon. On Thursday, Oct. 4, 2018, two ...