Earth’s First Trojan Asteroid discovered by NASA’s WISE
A "Trojan" asteroid has been discovered sharing Earth's solar orbit by astronomers studying observations taken by NASA's Wide-field Infrared Survey Explorer (WISE) mission. Trojans are asteroids that are gravitationally bound to a planet, but are not moons, because they do not orbit the planet. Instead they orbit one of the two stable points in front of or behind the planet, called Lagrangian points (L4 and L5 to be precise).
Non-Rocket Spacelaunch – Extraterrestrial Space Elevator Concepts
Earth is not the only planet that could have a space elevator. Variants of the basic space elevator design could also be built on other celestial bodies in the solar system. Most of those variants could fit into three categories…
