Yesterday, we took a look at the Andromeda Galaxy (aka M31) in Infrared and radio wavelengths. Today, we view it in the ultraviolet end of the spectrum. It took 11 images from the Galaxy Evolution Explorer (GALEX) satellite’s telescope to produce this UV portrait of the galaxy. While its spiral arms stand out in visible light images, they look like rings in UV because the image is dominated by light from hot, young, massive stars. The rings of intense star formation have been interpreted as evidence Andromeda collided with its smaller neighboring elliptical galaxy M32 more than 200 million years ago.
Image Credit: NASA