Artist's impression of Planet Nine – a suspected “wide-orbit” planet – with the Sun in the distance; Neptune's orbit is shown ...

Close stellar encounters could change the structure of our planetary system, potentially dooming Earth or other worlds to ...

How Many Planets Are There in the Solar System? There are 8 planets in our solar system. The planets orbit the Sun in elliptical trajectories, and they are all different in size, composition, ...

In the remote outer reaches of planetary systems, far beyond the orbit of known planets, enormous and mysterious worlds ...

Stars passing close to the sun could cause planets to collide, including with Earth, or even be ejected as rogue planets, new ...

When the Sun expands into a red giant, it will swallow the inner solar system and raise the temperature in the outer regions.

For decades it was thought that water was prevalent in the outer reaches of the Solar System early in its history, with comets and asteroids delivering moisture to Earth and the inner planets during ...

"Its occurrence is like finding a tropical seed in Arctic ice – indicating either an unexpected local environment or ...

The outer reaches of our Solar System continue to reveal a complex dynamical environment where the interplay of gravitational forces shapes the orbits of a myriad of distant bodies. Research in ...

For years, scientists have puzzled over why Earth and Mars are missing certain key elements. Now, a fresh study suggests ...

A recent study in Icarus suggests a wandering star could disrupt our solar system. Simulations reveal that a star passing ...

Among the planets, moons are more common in the outer reaches of the solar system. Mercury and Venus are moon-free, Mars has two small moons, and Earth has just one.