The simulation of the Solar System that came the closest to the observation was the presence of a small planet, between the ...

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 Earth. The authors dubbed it Planet Y.

A low-density, puffy planet orbiting relatively far from a young star in a nearly perpendicular orbit. What's going on?

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

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

Did NASA find another Earth? Scientists look to the sky to find a copy of our planet, and some experts think they may have ...

On October 6 1995, at a scientific meeting in Florence, Italy, two Swiss astronomers made an announcement that would transform our understanding of the universe beyond our solar system. Michel Mayor ...

Astronomers are investigating a strange class of exoplanets known as eccentric warm Jupiters — massive gas giants that orbit their stars in unexpected, elongated paths. Unlike their close-orbiting ...

Interstellar comet 3I/ATLAS has caught the interest of astronomers and amateur enthusiasts alike as just the third object to ...

The methane gas may constitute a rarefied atmosphere, or it may come from erupting plumes on Makemake’s surface.

An interstellar comet, 3I/ATLAS, is speeding through our solar system in 2025, marking only the third such visitor. Traveling ...