Eight years outbound from Earth, NASA's New Horizons probe passed the orbit of Neptune ... Pluto's enormous distance from Earth -- so far that it will take radio signals some 4.5 hours to cross ...

Neptune’s orbit is essentially circular and in the same plane as most planets (the ecliptic plane), while Pluto’s orbit is elliptical and tilts 17º to the ecliptic. So, if Pluto and Neptune ...

But Pluto's 248-year orbit around the sun takes it 17 degrees above and below the plane in which Neptune and the other planets travel. So their paths don't actually cross as they swap positions.

NASA calls it a cosmic coincidence. On Monday, NASA's New Horizons spacecraft crossed the orbit of Neptune on its way to Pluto. The celestial milestone occurred on the 25th anniversary of Voyager ...

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

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 ...

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.

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.