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 ...

While planets circle the sun in what's called and heliocentric orbit, they rarely fall together in what appears to the human ...

Stargazers will be treated to a rare seven-planet alignment in February. This is what scientists hope to learn.

Hernandez runs the planetarium at UTRGV and says all the planets in our solar system will be visible tonight. Six planets will be visible to the naked eye and eight can be seen if you have a telescope ...

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.

Planetary alignments aren't rare, but they can be when they involve six of the eight planets in our solar system.