Which is a mark of a galaxy formed by collapse?(1 point) Responses uniformly young stars uniformly young stars abundant gas and dust abundant gas and dust same age stars same age stars a mix of young and old stars
a mix of young and old stars
A mark of a galaxy formed by collapse is a mix of young and old stars.
A mark of a galaxy formed by collapse is "a mix of young and old stars". This indicates that the galaxy has undergone a process called hierarchical galaxy formation, where smaller galaxies merge together to form larger ones.
To arrive at this answer, we can eliminate the other options by understanding the characteristics of galaxies formed by different processes:
1. "Uniformly young stars": This reflects a galaxy that has experienced a recent burst of star formation, but not necessarily a collapse. Therefore, we can eliminate this option.
2. "Abundant gas and dust": This characteristic can be present in both collapsing and non-collapsing galaxies. It signifies that there are sufficient materials for future star formation, but it does not provide clear evidence of a collapse.
3. "Same age stars": This is a characteristic of galaxies that form through a process known as monolithic collapse. In this scenario, stars in the galaxy form at roughly the same time, resulting in a population of stars with the same age. Since the question asks for a mark of a galaxy formed by collapse, we can eliminate this option.
By process of elimination, we are left with "a mix of young and old stars" as the correct answer choice. This combination suggests that the galaxy has likely formed through the hierarchical merging of smaller galaxies, resulting in a mix of stars from different generations.