Our Galaxy: How big is Space?

What is the name of our galaxy?

• Milky Way

• Andromeda

• Proxima Centauri

• Kepler Galaxy

A galaxy is...

• a star and a collection of planets

• the planets that circle a star

• a collection of solar systems

• Everything. Just literally everything.

Our galaxy is about _____ lightyears wide.

• 100,000

• 220,000

• 4,000,000

• 1.87

A light-year is...

• the amount of light a star makes in one year

• the distance light travels in one year

• the time it takes to reach the outside of our solar system

• the distance between our star and the nearest star

ONE light year is about 5.8 ________ miles.

• million

• billion

• trillion

• quadrillion

Our galaxy probably contains _____ stars.

• 100-400

• 1,000,000-4,000,000

• 100,000,000,000-400,000,000,000

Most stars that we have observed have at least one planet

• true

• false

The thing at the farthest edge of our galaxy is called...

• Pluto

• The Kuiper Belt

• The Oort Cloud

• Proxima Centauri

Scientists have confirmed that at least _____ planets exist

• 8

• 356

• 3,900

• 18,000

That universe likely contains at least 2 ______ galaxies

• (two--just two galaxies)

• million

• billion

• trillion