The number of planets that orbit the sun depends on what you mean by “planet,” and that’s not so easy to define ...

Does our Solar System have 9 planets or only 8? Astronomers have gone back and forth on that a lot, with Pluto now being classified as a dwarf planet. However, out beyond Neptune there could be ...

Canadian astronomers have taken an extraordinary step in understanding how planets are born, using the James Webb Space ...

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

Mercury is the closest planet to the sun, followed by Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune. Mercury orbits ...

An object eight times the mass of Jupiter may have swooped around the sun, coming superclose to Mars' present-day orbit before shoving four of the solar system's planets onto a different course.

The exoplanet has a radius around 2.7 times and a mass about 8.2 times greater than Earth ... expands our understanding of the diversity of planets (just like this strange object in our Solar System).

Mars, Venus, Jupiter and Saturn should be visible to the naked eye, but with a telescope you can spot Neptune and Uranus.

you’re peering into the vast expanse of our solar system. Each planet orbits the Sun at vastly different distances—Mercury sits about 36 million miles, while Neptune is at a stately 2.8 ...