An object eight times the mass of Jupiter may have swooped around the sun, coming superclose to Mars' present-day orbit ...

Simpson and Chen ran mathematical models looking at how differently sized Earth-like worlds would have affected the rest of ...

All seven of the other planets in our solar system are about to become visible at once in a great planetary alignment – ...

When you first learned about the Solar System, you probably saw diagrams that made it look orderly, with planets arranged in ...

A new study claims it is possible an "alien visitor" could have warped our solar system during its earliest years.

The enormous visitor to our solar system may have been about 8 times the mass of Jupiter, and come nearly as close to the sun ...

The research, yet to be peer-reviewed, sheds light on what could have changed the orbits of several planets in the solar ...

The planets in our solar system orbit around the sun at different speeds in more or less a flat plane called the ecliptic. The varying orbiting speeds are why several of them can be roughly lined ...

Stargazers will be treated to a rare alignment of seven planets on 28 February when Mercury joins six other planets that are already visible in the night sky. Here's why it matters to scientists.

A planet-sized visitor possibly visited the solar system billions of years ago and permanently changed the cosmic neighbourhood by warping the orbital path of four outer planets of the system, a ...

The eight planets in our solar system orbit the sun in roughly the same plane, because they all originally formed from the same disc of debris around the sun. The line the sun traces across the ...