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

Asteroids are rocky objects that orbit the Sun, just like planets do. There are millions of asteroids of very different shapes and sizes. Some are almost spheres, like planets, but most are ...

The new exoplanet, Enaiposha, also known as GJ 1214 b has never been seen before and is now officially being called a "Super-Venus." ...

Different types of molecules have different ... A planet's mass, taken together with its physical size, tells us the planet's density. Density, in turn, tells us a lot about what a planet must ...

The appearance of planetary alignment across the sky is only an illusion, since the planets are positioned at different depths in space. "What makes it significant for this January is that we ...

Roughly half the size of our own Jupiter ... Similar gas giant planets can have vastly different atmospheric compositions with disparate cloud or haze properties. Located some 869 light years ...

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.