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

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 ...

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If there is some planet nine, or "Planet X" lurking out there, we have yet to find it. But there is some tentative evidence for it. As we have found more Pluto-like bodies known as Trans-Neptunian ...

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

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 ...

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

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