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

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 ...

Mercury joins the night sky to complete a 7-planet alignment just after sunset for the end of February. Saturn leaves our ...

All of our solar system’s planets are lining up to parade through the night sky at once. This extraordinary celestial event ...

Starting up again Saturday, a sweeping view of our solar system will glow in the night sky. The planetary alignment, or a ...

Stargazers will be treated to a dazzling six-planet "alignment" this January.

Baker said that there are other astronomical events that may be more interesting than the parade of planets. Baker said Mars ...

Beyond Neptune lies the Kuiper Belt, a vast expanse of icy bodies that may hold clues to the solar system’s formation. These ...

A shortcut for New Yorkers to spot some of the planets is to look for them when they are near the moon. On Feb. 1, Venus will ...

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

Ever since Isaac Newton famously talked about gravity, its dominance as a force in our solar system has been well known. It's ...