What is outer space?
The vast area beyond Earth that contains planets, stars, and galaxies
Astronomical Unit
What is at the center of our solar system?
The Sun
What is Earth spinning on its axis called?
Rotation
What force pulls objects toward each other?
Gravity
Why are space telescopes better than Earth telescopes?
They are outside Earth's atmosphere
What is 1 AU?
The distance from Earth to the Sun
What is the path and object takes around another object called?
Orbit
How long does Earth take to rotate once?
24 hours
What causes the Moon's phases?
What are satellites used for? (name one)
Communication, weather, GPS, or studying space
What unit is used to measure distances between stars and galaxies?
Light years
What is a solar system?
A star and all objects that orbit it
What does Earth's rotation cause?
Why do stars twinkle?
Because of the Earth's atmosphere
What is an observatory?
A building with powerful telescopes used to study space from Earth
About how far does light travel in one year?
About 6 trillion miles
True or False:
Planets stay in orbit because there is no gravity in space
FALSE! Gravity is what keeps them in orbit
What is Earth's movement around the Sun called?
Revolution
What two things affect gravity?
Mass and distance
How are space shuttles different from rockets?
They can be reused
How far away is the Andromeda Galaxy?
About 2.5 million light years
What galaxy do we live in?
The Milky Way
Why does the Sun appear to move across the sky?
Because the Earth is rotating
What causes stars to shine?
Nuclear fusion (hydrogen -> helium)