One summer night in 1877, American astronomer Asaph Hall was looking through his telescope in Washington, D.C. Mars was at its closest point to Earth in its orbit, and Hall had one question on his ...

Mars, the fourth planet from the Sun, is a subject of fascination for astronomers. Though significantly smaller than Earth, this red-hued world has two moons that continue to spark debate among ...

Japan is putting its Martian Moons eXploration (MMX) spacecraft through a series of tests ahead of its launch to Mars next year. MMX is a complex mission to collect samples from the moon Phobos and ...

Forbes contributors publish independent expert analyses and insights. I cover aerospace, astronomy & hosted The Cosmic Controversy Podcast. Mars' mysterious moons of Deimos and Phobos have long ...

A European spacecraft on a journey to study NASA's asteroid crash site did a quick pop-in of Mars on its way, capturing unprecedented images of Mars' lesser-known moon, Deimos. Mars has two moons, ...

NASA's Europa Clipper spacecraft is on a journey to Jupiter's moon, Europa, a frozen world believed to harbor a salty ocean beneath its icy crust — and possibly the conditions to support life. Credit: ...