A European-Japanese spacecraft has beamed back some of the best close-up photos yet of Mercury's north pole as part of only the second human survey of our solar system's innermost planet. The ...

Mercury takes only 88 Earth days to orbit the sun.

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

Mercury, the innermost planet in our solar system, is full of surprises! Join us for an in-depth look at its physical characteristics, surface features, and mysterious magnetic field, all captured in ...

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 ...

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

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

Mercury joins the night sky to complete a seven-planet alignment just after sunset for the end of February. Saturn leaves our ...

Here’s what you should know when you go outside to see for yourself: Yes, the planets are indeed lined up across our sky. No, ...