Some of the most beautiful sights in the universe are ones that we could never see with our eyes. One such example is this lovely composite of the Carina Nebula made with visible and radio light.
The visible light image is a wide-angle view of an active star forming region of our galaxy. This large complex of gas clouds can be seen from the Southern Hemisphere, but it is not as famous as its cousin, the Orion Nebula.
Over a year ago, astronomers using the Atacama Pathfinder EXperiment, or APEX, studied the parts of the nebula that are not visible to our eyes or to optical telescopes.
The orange "blobs" in this image represent the regions that glow as seen by a sub-millimeter telescope such as APEX. Most of this emission comes from dust which is warmed up by ultraviolet and visible light from the young stars that then radiates at longer wavelengths. Many of the young stars are extremely large, hot, and will not live for much longer in cosmic timescales.
However, not all of the gas in the nebula will actually form stars. Only about 10 percent of this gas is dense enough to start the star birth process, and this is pretty typical for our galaxy.