Which of the following statements about rich clusters of galaxies (those with thousands of galaxies) is not true?
A) They are sources of X-ray emission due to the presence of hot, intergalactic gas.
B) There likely have been numerous collisions among the member galaxies at some time in the past.
C) Galaxies in the central regions are predominantly spirals, while elliptical galaxies roam the outskirts.
D) They often have a very large, central dominant galaxy near their center, perhaps formed by the merger of several individual galaxies.
E) The speeds of the galaxies in the cluster indicate that most of the cluster mass is dark matter.
Question 2
Black holes with masses greater than a million solar masses explain the extremely rapidly moving stars and gas in the cores of galaxies.
Indicate whether the statement is true or false
All objects in the image are distant galaxies – not stars
A Cluster of Galaxies
The Rotation Curves of Four Spiral Galaxies
In the summer of 1793, a yellow fever epidemic struck Philadelphia, killing nearly 4,000. Tens of th
An engine will not run if the air–fuel mixture is either too rich or too lean.
Rich Energy Deposits