The infrared Spitzer Space Telescope had its 15th anniversary a few days ago. Here is an image of the
Trifid Nebula (M20) about 5500 light years away in the constellation Sagittarius.
In visible light pictures, you see the nebula divided into
three parts by dark dust lines. (This is where its name comes from.) In the infrared there are filaments of glowing dust clouds and newborn stars. These baby stars and embryonic stars are hidden in the dust in visible light images.
Image Credit: J. Rho (SSC/Caltech), JPL-Caltech, NASA