Astronomers left puzzled by the dimmest supernova ever seen

By Leah Crane

The faintest supernova ever seen has been spotted in a galaxy about 88 million light years away. It is so dim that it doesn’t seem to fit existing models produced to explain the faintest supernovae.

Viraj Karambelkar at the California Institute of Technology and his colleagues found the cosmic explosion, called SN 2021fcg, using the Zwicky Transient Facility in California. At its peak, it put out about three times less than the previous record holder for faintest supernova.

“It’s at least 100 …