Camera, Imaging, Digital, Sloan Digital Sky Survey CCD Array

The Sloan Digital Sky Survey (SDSS) is a continuing project to produce a digital map of the entire sky visible from Apache Point, NM. This map provides highly precise measurements of the multi-color brightnesses of all objects seen in the sky to a faintness 16 million times fainter than the faintest stars visible to the naked eye (what astronomers call 23rd magnitude). This original camera, installed in the late 1990s, is the core element in the imaging system that produced both the accurate positional maps required to isolate the candidate galaxies, together with their photometric, or brightness properties, and laid the basis for the determination of their radial velocities utilizing plug plates, an example of which is also in the collection.

An international consortium of universities and laboratories built this large-format mosaic detector device around a series of matched charge-coupled device (CCD) chips in two groups. Institutions included Princeton University, the University of Chicago, the Institute for Advanced Study, the Japanese Participation Group, Fermilab, the University of Washington, the Naval Observatory, and The Johns Hopkins University. Funding came from the Alfred P. Sloan Foundation and the National Science Foundation. Support also came from a Grant-in-Aid for Specially Promoted Research, from the Ministry of Education in Japan, the Japan Society for the Promotion of Science, and also Keith Gollust.