Science is literally in the dark when it comes to the birth of stars, which occurs deep inside clouds of gas and dust. These clouds are completely opaque to ordinary light. Now, a group of astronomers has discovered a new astronomical phenomenon that appears to be common in such clouds, and promises a new window onto the earliest phases of star formation. The phenomenon -- infra red light that is scattered by unexpectedly large grains of dust, which the astronomers have termed "coreshine" -- probes the dense cores where stars are born.
Stars are formed as the dense core regions of cosmic clouds of gas and dust ("molecular clouds") collapse under their own gravity. What happens during the earliest phases of this collapse is largely unknown. Enter an international team of astronomers who have discovered a new phenomenon which promises information about the crucial earliest phase of the formation of stars and planets: "coreshine," the scattering of mid-infrared light (which is ubiquitous in our galaxy) by dust grains inside such dense clouds.