For decades, Pluto remained one of the most mysterious objects in our solar system, until July 14, 2015, when NASA's New Horizons spacecraft became the first mission to visit it up close, capturing ...

NASA's New Horizons spacecraft made history by flying past Pluto, sending back groundbreaking data that would change our ...

Pluto is the tiniest planet in our solar system with a diameter of roughly 2,377 kilometers, making it even smaller than our moon. Check out these 7 rare photos of Pluto clicked by NASA.

The complex geology of Pluto also tells us about the early solar system. The surface of the planet was documented by NASA’s New Horizons mission, which flew by in 2015.

WASHINGTON (AP) — There’s a chaotic dance going on at the far end of our solar system, involving Pluto and five of its closest friends, a new study finds. Hubble Space Telescope images of ...

Pluto is the only planet (OK, now former planet) in our solar system discovered by an American. Astronomer Clyde Tombaugh spotted the dot in 1930 from Lowell Observatory in Flagstaff, Arizona.

The so-called “heart of Pluto” was first discovered in 2015, when NASA’s New Horizons space probe beamed back the first close-up images of the distant, demoted dwarf planet.

In the cold, distant reaches of the Solar System, far beyond Pluto, astronomers have just identified what could be a new dwarf planet. It's called 2017 OF 201, a rock that appears to be some 700 ...