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

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

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

All of our solar system’s planets are lining up to parade through the night sky at once. This extraordinary celestial event will see the sky scattered with seven visible planets in what is known as a ...

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

The formation of our solar system from a singular nebula raises an intriguing question: why did each planet develop with a ...

The planetary parade in February 2025 will see five bright planets in clear view and a special alignment of Mercury and Saturn ...

While the composition of gas and dust in a molecular cloud is fairly uniform, everything changes once a star begins to form.