A new study has proposed the existence of Planet Y, an alternative Planet Nine candidate that is smaller and closer to Earth ...

A new study suggests yet another theory for a possible extra planet in our solar system, likely of a size between Mercury and ...

If you think you've met the wildest exoplanet yet, you haven't learned about TOI-4507 b. This strange world breaks almost ...

While Planet Y has been not yet been directly observed, unexpected inclinations found in the orbits of roughly 50 distant ...

Just as Earth orbits the sun, most planets discovered beyond our solar system orbit a host star. But some are out there all ...

Astronomers have discovered new evidence that suggests the possibility of an unknown planet in our solar system's farthest ...

Space scientists look back on 30 years of exoplanet discoveries — from rows of massive ‘super-Earths‘ to worlds with ...

A mysterious space object named 2023 KQ14, nicknamed “Ammonite,” challenges theories about the mysterious and possible Planet ...

From lava worlds to gas giants, NASA says the variety of these worlds is staggering—and that signs of a further 8,000 distant ...

Mercury is tiny, barely bigger than the Moon. Its metallic core makes up 70% of the planet’s mass, vastly exceeding Earth’s ...