The Perseus molecular cloud (Per MCld) is a nearby (~1000 ly) giant molecular cloud in the constellation of Perseus and contains over 10,000 solar masses of gas and dust covering an area of 6 by 2 degrees. Unlike the Orion molecular cloud it is almost invisible apart from two clusters, IC 348 and NGC 1333, where low-mass stars are formed. It is very bright at mid and far-infrared wavelengths and in the submillimeter originating in dust heated by the newly formed low-mass stars.
It shows a curious ring structure in maps made by the IRAS and MSX satellites and the Spitzer Space Telescope and has been detected by the COSMOSOMAS at microwave frequencies as a source of anomalous "spinning dust" emission.
See also
Giant molecular cloud Orion molecular cloud IC 348 NGC 1333 Molecular cloud Spitzer Space Telescope Spinning dust
References
More on THE ASTROPHYSICAL JOURNAL http://iopscience.iop.org/0004-637X/656/1/293