Using the quick search there are shown up to three reports about H-alpha emission:
When a cloud of interstellar gas collapses to form stars, the stars range from massive to minute.Since the 1950s astronomers have thought that in a family of new-born stars the ratio of massive stars ...
Physik Astronomie |As this ionised region expands into space, the associated shock wave sweeps up a layer of the surrounding cold interstellar gas and cosmic dust. This layer becomes unstable and collapses under its own...
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