Sharpless catalog

The Sharpless catalog is a list of 312 HII regions ( emission nebulae ) with the intention of a complete list of these objects north of declination δ = -27 ° ( however it has also some nebula south of this survey). The first issue of 1953 ( Sh1 ) still contained 142 objects, the second and final version of 1959 ( Sh2 ) by Stewart Sharpless then 312 objects. The catalog also contains some planetary nebulae and supernova remnants.

In 1953, Stewart Sharpless of the United States Naval Observatory Flagstaff Station staff, where he analyzed HII regions in the Milky Way, based on the survey of the Palomar Sky Survey and was cataloged. From this work out, he published his catalog of HII regions in two editions, the first in the same year with 142 nebulae. The second and last edition was published in 1959 and contained 312 fog.

Sharpless coordinates of the first edition Sh1 based on the star catalogs of the Bonner Durchmusterung (BD) or the Córdoba - screening (CD). The second edition used coordinates of the epoch 1900.

In Sh2 have some coordinates in the Southern Hemisphere measuring deviations of about one arc minute. This can make it difficult to locate the objects sought significantly. Therefore, a revisionierter catalog by the name of BFS ( Blitz, Fich, and Stark) was issued. This contained 65 new items, 20 items were removed. Most of the remote objects were either already mentioned fog or remains.

The 312 entries in the Sharpless catalog sometimes overlap with the 110 in the Messier Catalog (M), the 7,840 of the New General Catalogue (NGC ) and the RCW catalog. Contemporary were the catalogs Gum and RCW, although this mainly covered the southern hemisphere.

Examples

Summary of examples of the second Sharpless catalog from 1958; Clicking on the picture will download the image description, the majority are either of different amateur astronomers of the European Southern Observatory, ESA or NASA

PK 349 01 1, Butterfly Nebula, RCW 124, Gum 60