Scale of the Universe Test

What is a light year?

• 365 days

• The distance light travels in a year

• The distance from Earth to Proxima Centauri

• The light the sun produces in a year

Astronomers must measure very large distances in space. The astronomical unit (AU) was defined to make some space measurements. Which of the following distances is equal to 1 AU?

• One billion kilometers

• The distance that light travels in a year

• The distance light travels in one second

• The distance between Earth and the Sun

Which of the following would most often be measured in light years?

• Distances between planets in our solar system

• Distances between the Sun and objects in our solar system

• Distances between stars and galaxies

• The distance between the Earth and the Moon

What are light years used to measure?

• Distances between objects in the universe

• The time it would take to travel between objects in the universe

• How fast light can travel in different mediums

• The brightness of stars in the sky

The star Alpha Centauri is 4.3 light years from Earth. What does this mean?

• It would take 4.3 years for a person traveling on the space shuttle to reach Alpha Centauri.

• Alpha Centauri’s distance from Earth is 4.3 times the distance of Earth’s orbit.

• Alpha Centauri is 4.3 billion miles away from Earth

• It takes 4.3 years for light from Alpha Centauri to reach Earth

How long will it take a person on Earth to see light from a star that is 500 light years away?

• One year

• 500 minutes

• 500 years

• Instantly

What is the term for when objects that are closer appear larger than object that are farther away?

• Relative Brightness

• Relative Size

• Relative Distance

• Absolute size

What is a star and all of the things that are controlled by that star’s gravity?

• Galaxy

• Universe

• Solar System

• Star

What is the term for all of space and everything in it?

• Galaxy

• Universe

• Solar System

• Star

What is a group of billions of stars, star systems, dust, and gas, all held together by gravity?

• Galaxy

• Universe

• Solar System

• Star