Pluto was long considered our ninth planet, but the International Astronomical Union reclassified Pluto as a dwarf planet in ...

Over the past decade, researchers have been puzzling through Pluto’s mysteries. Meanwhile, the New Horizons probe heads for interstellar space.

Since Pluto is located so far from the sun, it takes around 248 Earth years for Pluto to orbit the sun. Pluto’s orbit around the sun is not only a very long journey, it’s also elliptical, resembling a ...

Sedna, a distant dwarf planet three-quarters the size of Pluto, is inching toward the brightest star in our sky — and in 2076 ...

What processes during the formation of Pluto's largest moon, Charon, potentially led to it having cryovolcanism, and even an ...

As Pluto is the most distant of the nine planets, its 248-year orbit around the Sun is lengthy compared with human timescales. It is also the most eccentric: Pluto's heliocentric distance varies ...

Think you know Pluto? Think again. From its mysterious orbit to why it’s so hard to spot - even with Hubble - this video ...

Sedna will make its closest approach to the Sun in 2076, giving us a rare opportunity to visit the planetoid before it drifts ...

Pluto once held its place proudly as the ninth planet in our solar system,a distant, icy world on the edge of the cosmic frontier. But in 2006, everything changed. This in-depth explainer unpacks the ...

In the outer reaches of our solar system, far beyond the orbit of Pluto, lies Sedna, one of the most mysterious objects ever ...

Sedna will reach its closest approach to the Sun in 2076, providing a remarkable space-faring opportunity that won’t come ...

Close stellar encounters could change the structure of our planetary system, potentially dooming Earth or other worlds to ...