Rocky bodies called protoplanets were thought to have formed slightly earlier in the inner solar system than those beyond the ...

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, ...

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

Mercury is by far the smallest planet in the solar system, with only around 5.5% of both the mass and volume of Earth.Despite that diminutiveness, Mercury manages to be the second-densest planet ...

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

Our Solar System is full of mysteries, but if the inner planets are a puzzle, the boundary between the Solar System and interstellar space is a secondhand puzzle with half the pieces missing.

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

In the remote outer reaches of planetary systems, far beyond the orbit of known planets, enormous and mysterious worlds silently loop around their stars. Some drift as far as 10,000 times the distance ...

How did the Solar System's giant planets form? The Solar System formed from a collapsing gas cloud, with the vast majority of it becoming part of the Sun.The remaining 0.1% of matter formed a ...

Planets & Transits News: Planets define characteristics of astrological signs. Inner planets, like Sun and Mars, have frequent influence, while outer planets like Jupiter and ...