Why is an understanding of light important to astronomers?

What are the applications of electromagnetic waves

Arunner is training for an upcoming marathon by running around a 100-m-diameter circular track at constant speed. let a coordinate system have its origin at the center of the circle with the x-axis pointing east and the y-axis north. the runner starts at (x, y) = (50 m, 0 m) and runs 2.5 times around the track in a clockwise direction.

4. if you were an astronaut on the moon, what would you experience? what would you see from your perspective?