A powerful new observatory is the best hope yet for finding the elusive Planet 9, a large planet that some scientists say is ...

Astronomers have long suspected that an enormous, unseen planet is hiding somewhere far beyond Neptune, quietly shaping the ...

In a potential landmark discovery, scientists using the James Webb Space Telescope have obtained what they call the strongest ...

But some astronomers suspect that at the edge of our solar system there is another large planet, and they call it Planet 9. NPR's Nell Greenfieldboyce reports that astronomers have been hunting ...

But no one has actually spotted Planet 9. It's so far away ... was messing with the orbits of some small solar system bodies. "Vera Rubin is our best bet to find it in the next few years, probably ...

Carbon dioxide has been detected on a planet outside our solar system for the first time. The gas has been observed directly by the James Webb Space Telescope on four exoplanets, all belonging to ...