Here’s a picture taken by the Hubble Space Telescope of the spiral galaxy ESO 499-G37 against a backdrop of distant galaxies and fronted by a scattering of nearby stars. The faint, loose spiral arms are the bluish features swirling around the galaxy’s nucleus. This blue tinge is light from hot, young stars in the spiral arms. The arms of a spiral galaxy typically have large amounts of gas and dust, the stuff from which new stars are constantly forming.
Image Credit: NASA