Question

1. how can astronomers tell where new star formation is happening in interacting galaxie

○ by observing bright blue clusters
○ by locating dark spots in the galaxies
○ by only using visible light
○ by finding areas with no gas or dust

Explanation:

Newly formed stars are hot, massive, and emit intense blue light, forming bright blue clusters. Dark spots are typically dust clouds that block light (not indicators of star formation), astronomers use multiple wavelengths (not just visible light) to study star formation, and star formation requires dense gas and dust (so areas without these cannot form new stars).

Answer:

A. By observing bright blue clusters