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20 terms

IGCSE Astronomy

the 3rd planet from the sun
any natural satellite of a planet
the natural satellite of the Earth
(physics) the force of attraction between all masses in the universe
any celestial body orbiting around a planet or star
artificial satellite
man-made equipment that orbits around the earth or the moon
Take 24 hours to revolve around Earth and always above same point on Earth's surface - most communication satellites are in this orbit
polar orbit
orbit that allows a satellite to travel around the earth, from pole to pole, in a short time to provide broad photo coverage of the planet
low earth orbit
an orbit located a few hundred kilometers above the earth's surface
orbital period
the time required for a body to complete a single orbit
orbital radius
distance from a satellite to the center of the object it is orbiting
orbital speed
the speed at which a planet is traveling in its orbit
a relatively small extraterrestrial body consisting of a frozen mass that travels around the sun in a highly elliptical orbit
Solar System
sun, planets, and all the other objects that revolve around the sun
Milky Way
the name of our galaxy, a spiral galaxy that contains about 400 billion stars
a collection of star systems
a celestial body of hot gases that radiates energy derived from thermonuclear reactions in the interior
gravitational force
the force of attraction between all masses in the universe
everything that exists, including the sun, stars, all the planets, and outer space