This all-sky catalog, described in Monet et al. (2003), consists of positions, proper motions, magnitudes, and other measured quantities for 1,045,175,762 objects. The data were derived from digitizing scans of almost 7,500 photographic plates taken from various sky surveys during the interval from 1949 to 2002. The originating plate material includes five complete coverages of the northern sky and four of the southern sky.To be included in the catalog, an object must have been detected on two different surveys because isolated, single-survey detections are unreliable. For the earlier USNO-A catalog (which was essentially a two-color, one-epoch catalog), this meant that the object must have had detectable fluxes on both the red and blue plates, and this led to the exclusion of many faint objects with non-neutral colors. Also, the larger epoch difference in the southern survey coverage meant that objects with larger proper motions tended to be excluded. USNO-B1.0 attempts to fix both of these problems. An object detected in the same band at two epochs will be included in USNO-B1.0, as will objects that have significant proper motions, although it is still the case that objects with large motions and extreme colors may be omitted. The selection algorithm requires that spatially coincident detections must be made on any two of the surveys for an object to be classified as real and be included in the catalog.The catalog is expected to be complete down to V=21. Estimated positional accuracies are 0.2 arcsec, photographic magnitude accuracies are 0.3 mag, and the accuracy for distinguishing stars from non-stellar objects is 85%.

천리안(COMS)자료는 전지구, 확장북반구, 동아시아 영역의 구름탐지, 해수면온도, 지표면온도 등 자료를 제공합니다.

COSMOS is an astronomical survey designed to probe the formation and evolution of galaxies as a function of cosmic time (redshift) and large scale structural environment. The survey covers a 2 square degree equatorial field with imaging by most of the major space-based telescopes (Hubble, Spitzer, GALEX, XMM, Chandra) and a number of large ground based telescopes (Subaru, VLA, ESO-VLT, UKIRT, NOAO, CFHT, and others). Over 2 million galaxies are detected, spanning 75% of the age of the universe.This is an I band selected multi-color catalog for 2 square degrees centered on the COSMOS field at 10:00:28.6, +02:12:21. A detailed description of the catalog is given in Capak et. al. (2007) and it is recomended that you read this paper before using the catalog.