Spiral Arm
Spiral Arm - A spiral shape seen in spiral galaxies that winds from the nucleus outward and is visible due to the numerous bright blue stars, star clusters, nebula, dust, etc. located in or near the arm.
Shown is of a spiral galaxy with two major spiral arms, one of which the red arrow points. As shown, the arm spirals outward from the nucleus of the galaxy.
https://apod.nasa.gov/apod/ap160426.html
Author: Gerald Goodie and Dedrion Bacote, UCF Undergraduate 2017
Editor: Patrick Joiner, UCF Interdisciplinary Studies, Class of
2018
Senior Editor: M.M. Montgomery, Ph.D, UCF Physics