A new dwarf planet, discovered beyond Neptune and described as Pluto's 'cousin,' could void the hypothesis of a Planet X in ...

With Pluto spending 20 years of its 248-year orbit within the orbit of Neptune, you might expect that at some point, the two worlds could catastrophically collide. However, Pluto and Neptune never ...

As it orbits the sun once every 25,000 years, the celestial body 2017 OF201 travels beyond the Kuiper Belt into a region ...

Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune and Pluto. Many Americans grew up ... It has cleared the neighborhood around its orbit IAU members also concurred that dwarf planets ...

it will cross the orbit of Neptune, and be the closest to the sun of the two bodies. This happened most recently on Feb. 7, 1979-the first time since Pluto was discovered on Feb. 18, 1930.

So things stood for 65 years. Although Pluto's orbit was more elongated than the other planets' (and even crossed the orbit of Neptune—not the kind of thing you would expect a decent planet to ...

in its orbit around the sun, essentially laps a planet. While Mercury retrograde is the best-known and most maligned of retrogrades, Venus, Mars, Jupiter, Saturn, Uranus, Neptune, and Pluto all ...

Neptune’s largest moon, Triton, and the dwarf planet Pluto may have shared a common origin before being separated in the early solar system, an analysis of their composition suggests.

Neptune, Pluto. Pluto was last and least of them. An icy dwarf only half the size of the United States, it was on average 3.7 billion miles from the sun. It also has a decidedly strange orbit that ...