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

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

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

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

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 ...

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 ...

In the depth of winter, a sweeping view of our solar system will glow in the night sky. In total six planets will be visible, ...

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 appear just above the crescent moon. On the third day of the month, ...

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 ...

Although it's being mistakenly promoted as a "rare planetary alignment," one of the best "planet parades" in half a century ...