Milky Way Galaxy

Where in the disk are we (or how far from the center are we)?

Imagine that you could travel at the speed of light. Starting from Earth, how long would it take you to travel to the center of the Milky Way Galaxy?

• It would happen in an instant.

• 25 years

• 250 years

• 2,500 years

• 25,000 years

What do the disks of other spiral galaxies look like?

What does observing the light from stars in other galaxies tell us?

Where is the missing mass?