For a long time, children learning about space in school were taught that there were nine planets in our solar system. Then, ...

For years, the idea of a mysterious “Planet Nine” lurking on the edges of our solar system has captivated astronomers and ...

Ever since Pluto was demoted from planet status, astronomers believe a real Planet Nine exists in the solar system ...

Ever since William Herschel discovered Uranus in 1781, astronomers have been eager to find new planets on the outer edge of ...

Sign up for CNN’s Wonder Theory science newsletter. Explore the universe with news on fascinating discoveries, scientific advancements and more. Our solar system ...

We know from The Lord of the Rings that Tolkien crafted endless stars in his legendarium, but are there other planets too?

Aside from the solar system once again having nine planets—which it had before Pluto’s demotion in 2006—the discovery of a distant Earth-mass planet would have profound implications for ...

5️⃣ ‘Saddest thing’: When crews in Rome built a tiny temporary pool in front of the famous Trevi Fountain for tourists to ...

How many planets are there in our solar system? Nine? Eight? Twelve? Hundreds? I know many will insist there are nine, with Pluto as the ninth planet, but ...

The search for Planet Nine, a hidden world beyond Neptune, is heating up as scientists prepare to use a powerful new telescope.

In 2006, the International Astronomical Union reclassified it as a ‘dwarf planet’, and our Solar System dropped from having nine planets to eight.