The Universe Flashcards
What is the Universe?
A large collection of billions of galaxies.
Mostly empty space.
What is a galaxy?
A large collection of stars.
They rotate.
Galaxies are often millions of times further apart than the stars are within a galaxy.
Where is the Sun in the Milky Way?
It is about half way along one of the spiral arms of the Milky Way.
What is the name of the force which keeps the stars together in the galaxy?
Gravity
There are billions of stars (including the Sun) in the….
Milky Way Galaxy.
Our solar system is a part of a ….
… huge galaxy.
(There are billions of galaxies).
How far apart are neighbouring stars in the galaxy?
Often millions of times greater than the distance between planets in our solar system.
What does out solar system orbit?
The Sun
What are planets?
Large objects that orbit a star.
Name the eight planets in our solar system (in order from the Sun).
Mercury
Venus
Earth
Mars
Jupiter
Saturn
Uranus
Neptune
Name a Dwarf planet.
Pluto
What are Dwarf planets?
Planet-like objects that aren’t big enough to be planets.
What are moons?
A type of natural satellite (not man-made). They orbit planets with almost circular orbits.
What is a satellite?
An object that orbits a second, more massive object.
What are artificial satellites?
Ones humans have built. They usually orbit the Earth in fairly circular orbits.