Space Flashcards
What speed must you be at to escape the earths orbit
11,200 m/s
What speed must you be at to orbit the earth
7,600 m/s
centripetal force
Force, needed for circular motion, which acts towards the center of a circle.
What is the technical term for moons
Natural satlitlites
Dwarf planet
An objecting orbiting a star that is massive enough to be rounded by its own gravity but has not cleared the neighbourhood of other objects and is not a satellite.
Satellite
A body that orbits a planet. For example, the moon is a natural satellite of the Earth but communication satellites are artificial satellites of the earth.
asteroid
A rock in space. Asteroids orbit the Sun but some may cross the Earths orbit, producing a risk of collision.
Elliptical
Shaped like an ellipse. Oval or egg-shaped
Comets
A ball of icy rock that follows an elliptical orbit around the sun
What happens when a comet approaches the sun
It vaporises, meaning it turns into a gas and produces a distinctive tail
A stable orbit
Is one which the satellite’s speed is just right - it will not move off into space or spiral into the Earth will travel around a fixed path.
polar orbits
Polar orbits take the satellites over the Earth’s poles. The satellites travel very close to the earth as a low as 200k above sea level. They travel at almost 8000m/s
Geostationary orbits
Take 24 hours to orbit the earth, so satellite appears to remain in the same part of the sky when viewed from the ground. These orbits are much higher than polar orbits. (Typically 36,000km) So the satellite’s travel more slowly around (3000m/s)