Mars's moon Phobos is so strange that no one knows how it formed. But a forthcoming mission could solve this mystery - and a ...

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

A New Understanding of the Outer Solar System’s Structure The discovery of these distant objects, combined with the ...

There are also many in a region beyond Neptune called the Kuiper Belt. The solar system also contains small objects called comets. Comets are similar to asteroids, but are made of ice, dust and ...

However, the disk of the Solar System is relatively warped, and the orbits of its planets are slightly tilted and elliptical. It is quite possible that some heavy object entered the protoplanetary mix ...

Without a firm lower limit on size or mass, we’re forced to say the solar system has hundreds of planets—maybe thousands. Objects need to be at least 400 km or so in size to round out via self ...

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

The Saturn typically ranks as the 7th brightest object,. It is visible to the naked eye and can be seen as a prominent celestial body in the night sky ...

The Kuiper Belt, a vast region of icy objects ... solar system’s formation, extends far beyond Neptune and is home to Pluto and other dwarf planets. Astronomers believe that Planet Nine could be ...