The Pleiades
The Pleiades The Pleiades star cluster is well known for the striking visible nebulosity that envelopes the cluster’s brightest stars, scattering their light like fog around a streetlamp.Radio and infrared observations in the 1980s established that this nebulosity results from a chance encounter by the young stars of the Pleiades with an interstellar cloud, rather than being caused by debris from the cluster’s formation. New data obtained at Kitt Peak National Observatory suggest that the Pleiades are actually encountering two clouds, giving rise to an extraordinary and previously unknown occurrence: a three-body collision in the vast emptiness of interstellar space.Known as the Seven Sisters for the seven stars said to be visible with the naked eye, the Pleiades (M45) consists of more than 500 stars roughly 100 million years old in a cluster located about 400 light-years from Earth. NOIRLab/NSF/AURA