Which of the following is a true statement about the spiral arms of our galaxy?

Question

Quizplus · Accepted Answer

The spiral arms of our galaxy are the crests of a density wave, meaning they are areas where the concentration of gas and dust is greater than in other parts of the galaxy. As stars move through the arms, they experience gravitational forces that cause them to slow down and even clump together. However, stars are not permanently confined to the arms and can eventually drift away. Option A is incorrect because the spiral arms are not made of matter blown outward from the center of the galaxy. Option B is incorrect because stars are not permanently trapped in the spiral arms. Option D is incorrect because spiral arms have completed many rotations about the galactic center.

Which of the Following Is a True Statement About the Spiral