Introduction of Galaxies
PHY 111 S. Alexander
Characteristics of Galaxies
Three classifications of galaxies exist: Elliptical, Spiral and Irregular. The three galaxies differ in
composition, size, shape and star formation as well.
In the lab activity for Tutorial #14, which graph indicates a less massive planet in a closer orbit?
(On the Lab Activity page of Tutorial #14-the last page of the tutorial; consider the graph in the upper
left-A; upper right-B; lower left-C; lower right-
If you get pulled over for running a red light and claim that the light was Doppler-shifted to green and
the police officer believes you, but still writes you a ticket, what is the ticket mostly likely for?
Which factor is cleary dominant in causing Mars' cold surface temperature?
a. Mars high contenet of atmospheric greenhouse gases
b. Mars' farther distance from the Sun
c. Mars' high albedo
d. [None of the factors in the other three choices are
The distance between the Milky Way and Andromeda galaxies is about how many time their