The Andromeda Galaxy is 2 million light years away from the Milky Way.  How far away is the Andromeda Galaxy?

Most of the dark matter in a galaxy is located in the ________ which allows the more luminous matter to rotate around the center of the galaxy at a faster speed than predicted by Kepler's 3rd Law.

How many neutron stars are estimated to be in the Milky Way galaxy?   10         2000         30,000         100 million         100 billion

An astronomer in an imaginary Universe observes a small patch of the sky (0.005% of the total) with very deep observations and finds one million galaxies. How many galaxies can they estimate to be present in the whole Universe? 10 billion 20 billion 50 billion O 70 billion

Which of these colors of light passes most easily through interstellar clouds?  a Green light  b Red light  c Blue light  d Violet light

Figure 2 shows the "rotation curve" of NGC 2742. It plots the “radial velocity (V)" (how fast material is moving either toward or away from us) that is measured for objects at different distances (R = radius") from the center of the galaxy. The center of the galaxy is at 0 kpc (kiloparsecs) with a speed of 9 km/sec away from us. (These velocities have been corrected for the observed tilt of the galaxy and represent true orbital velocities of the stars and gas.) 200 100 U4779 -100 As you can see, one side of the galaxy is moving with a negative velocity (spinning toward us), while the other side has a positive velocity (spinning away from us). Using Newton's gravity equation, we will be able to determine the gravitational mass of the entire galaxy and how the mass varies versus distance from the galaxy's center. -200 -8 8 -4 Radius (kpc) Read the following text carefully and follow the instructions: Select five radii spaced evenly from 0-10 kpc across the galaxy. Your selections should…

Astronomers estimate the mass of the stars in a certain galaxy to be about 3.0e40 kg, and the total mass of this galaxy to be about 1.2e41 kg. The amount of the galaxy’s mass is made up of dark matter is_____ percent.

The hydrogen Balmer line has a wavelength of 486.1 nm. It is shifted to 565 nm in a galaxy's spectrum. What is the radial velocity (in km/s) of the galaxy? (Indicate the direction with the sign of your answer.)