LEO, GEO, L2, SSO—oh my! The many types of useful orbits can get complicated fast, but our handy guide will help you make sense of it all. Reading time 1 minute Nearly 140 rockets have flown to space ...

Ever since the telescope was invented in 1608, astronomers have striven for bigger and better telescopes. When it comes to instruments to observe the sky, bigger really is better whether you are ...

Satellites and spacecraft in the vast region between Earth and the moon and just beyond—called cislunar space—are crucial for space exploration, scientific advancement and national security. But ...

Modeling suggests that Earth-mass planets could maintain stable S-type orbits in the habitable zone around the primary star ...

Mathematicians think abstract tools from a field called symplectic geometry might help with planning missions to far-off moons and planets. In October, a Falcon Heavy rocket is scheduled to launch ...