General Astronomy - Spring
2007
Homework #8 - due March 26
1. List three
different types of galaxies and
describe their stellar orbits and gas content.
2. How do astronomers measure distances of hundreds to thousands
of Mpc?
3. Describe how an observer at a distance
of 7 billion light years away from us would see the expansion of the
Universe.
4. Assuming the Hubble constant is 60 km/s/Mpc, estimate the age of the
Universe.
5. A galaxy has a measured recession velocity of 8,000 km/s. How
far away is it? (Assume that the Hubble constant is 71 km/s/Mpc.)