A region of glowing gas in the Sagittarius arm of the Milky Way galaxy, NGC 3576 is located about 9,000 light years from Earth. Such nebulas present a tableau of the drama of the evolution of massive stars, from the formation in vast dark clouds, their relatively brief (a few million years) lives, and the eventual destruction in supernova explosions. The diffuse X-ray data detected by Chandra (blue) are likely due to the winds from young, massive stars that are blowing throughout the nebula. Optical data from ESO are shown in orange and yellow.
Image Credit: X-ray: NASA/CXC/Penn State/L.Townsley et al, Optical: ESO/2.2m telescope
Explanation from: https://www.nasa.gov/mission_pages/chandra/multimedia/NGC3576-glowing-gas-milky-way.html