Once the quirky underdog of our solar system, Pluto held planetary status until 2006, when it got a cosmic demotion that still stings space fans. Discovered in 1930, Pluto was the ninth planet for ...

Pluto was reclassified as a dwarf planet in 2006. Our solar system may have a ninth planet after all, researchers say. The possibility that an additional planet may be hidden far into the solar system ...

New high-contrast images from SPHERE show a stunning variety of debris disks shaped by collisions of tiny planet-building bodies. The structures often resemble our asteroid and Kuiper belts, hinting ...

A recent research paper suggests that a planet may exist far beyond Neptune — less than 20 years after the previous ninth planet, Pluto, was demoted. That research paper, accepted last month for ...

When you buy through links on our articles, Future and its syndication partners may earn a commission. A composite image comparing the relative sizes of our solar system's known dwarf planets, ...

SPHERE’s detailed images of dusty rings around young stars offer a rare glimpse into the hidden machinery of planet formation. These bright arcs and faint clouds reveal where tiny planet-building ...

On July 14, 2015, NASA's New Horizons spacecraft arrived at Pluto for the first time. The craft flew within 7,700 miles of the planet and is sending back reams of data and the highest resolution ...

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 ...

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, its ...

When I was a kid, there were nine planets. Now we know of thousands! But that includes exoplanets, alien worlds that orbit alien suns. Only eight planets call our solar system home. Or there might ...