orbits
6 questions tagged orbits — spanning every one of the seven Ws.
What is a Lagrange point?
A Lagrange point is a spot in space where the gravity of two large bodies, like the Sun and Earth, balances a spacecraft's orbital motion so it can stay in position with little fuel.
What is low Earth orbit?
Low Earth orbit, or LEO, is the region of space close to Earth, usually up to about 2,000 kilometers above the surface. Satellites there circle the planet quickly and are easier to reach.
How fast do planets move around the Sun?
Planet speeds vary from about 47.9 kilometers per second for Mercury to about 5.4 kilometers per second for Neptune, depending on distance from the Sun.
What is a geocentric orbit?
A geocentric orbit is any orbit around Earth. The Moon is not in a geocentric orbit because it orbits Earth, but artificial satellites are.
What is a perihelion?
Perihelion is the point in an object’s orbit when it is closest to the Sun. Earth reaches perihelion in early January each year.
How do scientists launch a satellite into a specific orbit?
They aim the rocket to reach the right speed, altitude, and direction, then use engine burns to fine-tune the orbit. The launch site and Earth’s rotation help determine the possible paths.