The Milky Way: Crash Course 37

What shape is the Milky Way galaxy described as?

• A spherical cloud

• A vast, flat, disk-shaped collection

How many major spiral arms does the Milky Way have?

• One

• Two

What is located in the center of the Milky Way?

• A black hole

• A bar of old red stars

How did ancient Greeks describe the Milky Way?

• As a celestial chariot track

• As a path of stars

What did Galileo discover about the Milky Way?

• It is a nebula

• It is made up of thousands of stars

Why is star counting not an effective method to map the Milky Way?

• Because of interstellar dust

• Because the galaxy is too large

What phenomenon are the spiral arms of the Milky Way compared to?

• Traffic jams

• Ocean waves

What role do massive stars play in the appearance of spiral arms?

• They make the arms appear blue

• They make the arms appear red

How long is the bar in the center of the Milky Way?

• 5,000 light years

• 20,000 light years

What is at the very center of the Milky Way?

• A cluster of young stars

• A massive black hole