What evidence supports the idea that a collision between two spiral galaxies might lead to the creation of a single elliptical galaxy?
A)observations of some elliptical galaxies surrounded by shells of stars that probably formed from stars stripped out of smaller galaxies
B)the fact that elliptical galaxies dominate the galaxy populations at the cores of dense clusters of galaxies
C)observations of some elliptical galaxies with stars and gas clouds in their cores that orbit differently from the other stars in the galaxy
D)observations of giant elliptical galaxies at the center of dense clusters that may have grown by consuming other galaxies
E)all of the above

Question

Quizplus · Accepted Answer

Observations of shell structures around some elliptical galaxies (A) suggest that these galaxies have grown through mergers with smaller galaxies. Additionally, the dominance of elliptical galaxies in the cores of dense galaxy clusters (B) suggests that mergers have played a significant role in their formation. The observation of different orbital patterns of stars and gas in the cores of some elliptical galaxies (C) is also consistent with the idea that they have formed through mergers. Finally, the presence of giant elliptical galaxies at the centers of dense clusters (D) suggests that these galaxies have grown through the consumption of other galaxies, which is consistent with the idea that they have formed through mergers.

What Evidence Supports the Idea That a Collision Between Two