Author Question: The Earth never passed through the cratering stage in planetary development. Indicate whether the ... (Read 81 times)

khang · **on:** Jul 27, 2018

The Earth never passed through the cratering stage in planetary development.

Indicate whether the statement is true or false

Question 2

Centaurus A is a radio galaxy that has a visible galaxy at the center. This central elliptical galaxy of Centaurus A is encircled by a ring of gas and dust, different from most elliptical galaxies. The dust ring orbits about an axis that is perpendicular to the axis of rotation of the elliptical galaxy. What does this suggest about this central elliptical galaxy of Centaurus A?

a. The radio jets have caused the dust disk to be driven around the elliptical galaxy.
b. There are at least two black holes at the center of the elliptical galaxy.
c. Centaurus A is probably the result of a merger of an elliptical galaxy and a spiral galaxy.
d. Dust is produced as the jets interact with the intergalactic medium.
e. Elliptical galaxies often contain dust that forms a disk along their rotation axis.