Friday, May 5, 2017

Our Galaxy and Other Galaxies


2 comments:

  1. You said the halo of a galaxy contains globular structures which are older clusters of stars. What would the main differences be in these clusters compared to newer clusters of stars?

    ReplyDelete
  2. So I understand how we classify spiral galaxies by how tightly their arms are wound, but do we know why they are different tightnesses?

    ReplyDelete