Astronomy Flashcards
1
Q
What is a planet and what are its characteristics?
A
A planet is an object in orbit around a star with three important characteristics:
- it has a mass large enough for its own gravity to give it a round shape
- it has no fusion reactions
- it has cleared its orbit of most other objects
2
Q
What is the definition of a planetary satellites? Give two examples.
A
A body in orbit around a planet, such s moons and man-made satellites.
3
Q
What is the definition of a comet?
A
Small irregular bodies made up of ice, dust and small pieces of rock which orbit the Sun with highly eccentric elliptical orbits.
4
Q
What are solar systems?
A
A collection of planets and their moons orbiting a sun
5
Q
What is a galaxy?
A
A galaxy is a collection of stars, and interstellar dust and gas.