Under the planet definition supported by Sykes, our solar system would have 13 planets, although more might be found in the future beyond the orbit of Pluto.

With thousands of exotic exoplanets known, the worlds of our solar system may seem rather dull. Trust us, they’re not.

Go look at The Planets Today. Notice anything strange? The planets are all on one side of the Solar System, with Earth somewhere in the “middle” of the cluster. While this is normal, natural ...

Scientists think that the gravitational influence of a tenth planet that is roughly the size of Mars could be the cause of strange orbits in our solar system.

Learn about the different planets in our Solar System. Find out their size, temperature and distance from the Sun in this Scotland Second Level Science article.

Although hundreds, or perhaps thousands, more solar system bodies may eventually join the list, the IAU officially recognizes just five dwarf planets at the moment.

This infographic displays some illustrations and planetary parameters of the seven planets orbiting TRAPPIST-1. They are shown alongside the rocky planets in our Solar System for comparison.

Astronomers have found new evidence that a mysterious ninth planet may be hiding at the edge of the solar system - rewriting what we know about the cosmos again. An international team from Taiwan ...

Last week, astronomers said they discovered evidence of a ninth planet in our solar system. It may be a super-Earth, something scientists didn't think we had here, says astrophysicist Adam Frank.

Have you ever wondered what our solar system looked like 3.8 billion years ago? Were the planets we know today anything like their current forms, or were they completely different? In this video ...