Almost one in five exploding stars in nearby galaxies is simply not seen, astronomers have determined. For galaxies further out, that fraction doubles. This finding clears the way for these stellar beacons to be used as a good measure of how fast galaxies made stars earlier in the Universe's history. Key evidence for this "body count" of missing supernovae came from detailed studies of the galaxy Arp 299, made with the 8.2-m Gemini North telescope. Read more