•Question 2 Observationsof galaxies and
clusters of galaxies indicate that roughly ____ percent of the universe is dark matter.
a.5%b.25%c.50%d.75%e.
95%
•You have to look this one up, but it is a number you
should know.
•
•Question 3 What is the most common type
of galaxy, based on what we see in our own Local Group?
a.irregular
galalaxies b.flocculant spiral galaxies c.grand design spiral galaxies d.giant ellipticals e.dwarf ellipticals
•This one you should know from the figure of the Local
Group in the slides/text. I’d make sure I knew this for the exam!
•
•Question 4 An elliptical galaxy could
•a.evolve into an irregular galaxy when it has used up
all of its gas and dust.
•b.be
formed from the collision and merger of spiral galaxies.
•c.become a starburst galaxy if it were to move
through the hot intergalactic medium of a cluster.
•d.evolve from a single spiral galaxy when that spiral
used up all of its gas and dust.
•Elliptical galaxies have already used up their gas
and dust, and it is thought they can
be formed from spiral mergers.
•