There's a new nickname for the icy world next up for the spacecraft that explored Pluto: Ultima Thule.
A record-tying eighth planet has been found in a faraway solar system, matching our own in number.
Move over Saturn! Scientists have found a ring around an unassuming mini-planet in our Solar System to debunk the theory that only giant planets can be so...
NASA's New Horizons spacecraft is now halfway between Pluto and its next much, much smaller stop.
A team of scientists seeking to restore Pluto to planethood launched a campaign on Tuesday to broaden the astronomical classifications which led to its...
The deep icy basin in Pluto's heart-shaped region may be a natural sinkhole.
Evidence is mounting for an ocean at Pluto, buried beneath its frozen heart.
Imagine a planet with triple sunrises and sunsets every day for part of the year, and nonstop daylight at other times.
Scientists reported Wednesday they finally have "good evidence" for Planet X, a true ninth planet on the fringes of our solar system
The recent discovery of an Earth twin has boosted chances there is intelligent life on other planets.
The first close-up views of Pluto show mountains made of ice and a surprisingly young, crater-free surface, scientists with NASA’s New Horizons mission said...
We’ve made it to Pluto by NASA’s calculations, the last stop on a planetary tour of the solar system a half-century in the making.
On the eve of NASA's historic flyby of Pluto, scientists announce that the New Horizons spacecraft has nailed the size of the faraway icy world
There’s a near-perfect heart shape on Pluto’s rusty red surface.
There's a near-perfect heart shape on Pluto's rusty red surface. The dwarf planet is dotted with bright points which may be ice caps, and a mysterious dark...
NASA said Monday it expects the New Horizons spacecraft to be back in service Tuesday after a computer glitch on the weekend threatened its upcoming historic...
LOS ANGELES (AP) - A NASA spacecraft for the first time has arrived at a dwarf planet to begin a 16-month exploration.
Peering into the far reaches of the solar system, astronomers have spied a pink frozen world 12 billion kilometers from the sun.
Uranus is a lopsided oddity, the only planet to spin on its side. Scientists now think they know how it got that way: It was pushed over by a rock at least...
The spacecraft team that brought us close-ups of Pluto will ring in the new year by exploring an even more distant and mysterious world.