After a decade-long search, some scientists say a growing number of clues point to the existence of a hidden planet in the Kuiper Belt beyond Neptune — and they may soon have the opportunity to find ...

Exoplanets can be quite different from Earth, but occasionally researchers find one that gives a sneak peak into what the ...

Ever since NASA's New Horizons sent back the first-ever photos of Pluto in 2015, the dwarf planet's mysterious heart ... roughly the size of Arizona from north to south. Pluto was discovered ...

Although Venus is commonly nicknamed "Earth's twin" since it is about the same size and mass, these two iron planets couldn't be more different, especially when you compare how well their ...

Asteroids are rocky objects that orbit the Sun, just like planets do. There are millions of asteroids of very different shapes and sizes. Some are almost spheres, like planets, but most are ...

Earth grew to its final size through one last major collision with another ... Different types of meteorites coming from the asteroids left over in the solar system after planet formation have ...

Just six light-years from the solar system — in cosmic terms, our backyard — exists a world about half the size ... planets. In addition to discovering Barnard’s b — a completely different ...

With planets so hot they rain iron ... just as a series of numbers and digits describing their different orbital parameters and size, the graphic adding texture, color and shape as the real ...

“Scientists come in different personality types ... coauthored an August 2017 paper suggesting the presence of a Mars-size planet in the Kuiper Belt, but she’s not ruling out the Planet ...