There are a couple of ways that scientists can date planets, so which planets formed first in our solar system?

A newly discovered warp in the outer Solar System may have been created by a small, rocky world, much closer to the Sun than ...

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

Voyager 1 has been exploring the cosmos for decades, but when it reached the edge of the solar system, it found something ...

Astronomers are investigating a potential hidden planet, dubbed Planet Y, far beyond Neptune. Its gravitational pull is ...

A newly discovered dwarf planet could hold the key to unlocking the mysteries of our solar system’s outer reaches — but what ...

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 ...

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

"It shows that Makemake is not an inactive remnant of the outer solar system, but a dynamic body where methane ice is still ...

The Hubble Space Telescope captured footage of Jupiter, Saturn, Uranus and Neptune in 2021. See them spin in this time-lapse. Credit: SCIENCE: NASA, ESA, Amy Simon (NASA-GSFC), Michael H. Wong (UC ...