The odd interstellar object that zoomed through the inner solar system last October might be an alien reconnaissance spacecraft, a new study suggests.
Learn more about NASA's New Horizons mission, which performed history's first flyby of the Pluto system on July 14, 2015.
The first known interstellar visitor to the solar system, 'Oumuamua, highlights how life could also spread between the stars, and perhaps even across the galaxy, two new studies find.
A spacecraft orbiting the dwarf planet could use Pluto's moon Charon to make important orbital changes.
One month from today, Mars will welcome a new robotic resident that seeks to probe the planet's innards.
In less than 10 weeks, NASA's New Horizons spacecraft will explore the most distant target ever visited by a spacecraft. Mission team members don't know what to expect — and that's part of the fun.
Whether Mercury formed from a single collision or multiple impacts, the iron-rich planet is probably a rare breed.
Evidence of a big, unseen world in the extreme outer solar system continues to mount, giving astronomers more and more confidence that "Planet Nine" is real.
Moons could possess moons of their own. Kepler-1625b-i, a newfound candidate to be a giant alien moon, may even possess one or more moons that once had habitable surfaces, a new study finds.
When skywatchers acquire their first telescope, I suspect there are two objects at the top of their observing list: the moon and the ringed planet Saturn.
NASA's New Horizons spacecraft successfully completed a brief engine burn on Oct. 3, the first maneuver in which it was able to rely on actual photographs it had already taken of its eventual target.