Before the Voyager 2 flyby of Uranus and Neptune, these two distant planets were thought to be cold, dead worlds on the outskirts of the solar system. The historic spacecraft visit, however, revealed ...

Uranus and Neptune remain two of the most mysterious objects in the solar system, primarily because they have been visited only by NASA's Voyager 2 spacecraft in 1986 and 1989, respectively. Their ...

Astronomers have spent years searching for a possible hidden giant planet far beyond Neptune. Unusual orbits among distant Kuiper Belt objects have fueled the Planet Nine theory, but recent ...

Diamond rain? Super-ionic water? These are just two proposals that planetary scientists have come up with for what lies beneath the thick, bluish, hydrogen-and-helium atmospheres of Uranus and Neptune ...

Nearly a decade after astronomers first proposed that a massive, unseen world is warping the paths of the most distant known ...

See more of our trusted coverage when you search. Prefer Newsweek on Google to see more of our trusted coverage when you search. We might have been very wrong about exactly what lurks below the ...

In space, planets are supposed to orbit their stars in roughly the same direction that the star itself spins. It is a rule ...

When Voyager 2 flew by Uranus and Neptune 40 years ago, astronomers were surprised that it detected no global dipole magnetic fields, like Earth's. The explanation: the ice giants are layered and ...

Jupiter, Saturn, Uranus and Neptune did not always have their current positions in the solar system. According to the planetary-instability model, they were born a little closer to the Sun and closer ...