The Sharpless Catalog

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Sh 2-31

Coordinates: (7.21°, -2.18°)
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Sh 2-29, Sh 2-31, and Sh 2-32 are a group of three nebulae next to the much larger Lagoon nebula. This group is combined together in the RCW (RCW 146c) and Gum (Gum 75) catalogs.

Avedisova lists two ionising stars for Sh 2-31: the O7V+O9V multiple HD 165921 and the B1 V multiple HD 166107.

Sh 2-32

Coordinates: (7.29°, -2.03°)
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Sh 2-29, Sh 2-31, and Sh 2-32 are a group of three nebulae next to the much larger Lagoon nebula. This group is combined together in the RCW (RCW 146c) and Gum (Gum 75) catalogs.

Also called IC 1274 and LBN 33, Sh 2-32 is near a major gamma ray source and numerous X-ray sources and has embedded OB stars. Avedisova lists two ionising stars, including the B1 V class CD -23 13997.

Sh 2-33

Coordinates: (8.34°, 36.35°)
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The faint red glow of the nearby molecular cloud MBM 38.

You can view a more detailed image of this nebula here.

Sh 2-34

Coordinates: (8.72°, -0.51°)
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This large diffuse HII region, also called LBN 38, is near the Sgr OB1 association and the Lagoon nebula. According to Sharpless, it is associated with the B1 star HD 165516, which Humphreys places in the Sgr OB1 association. Gum also mentions the Wolf-Rayet star WR 111.

Sh 2-35

Coordinates: (10.95°, -1.65°)
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Sh 2-35 and Sh 2-37 are part of a 130 thousand solar mass giant molecular cloud. Sh 2-35 appears along the western edge of this cloud. Sharpless connects this nebula to a number of stars, the hottest of which is the B0 IVPE star HD 312973, which Humphreys locates in the Sgr OB7 association.

SIMBAD reports that HD 312973 is actually an O-class star.

Sh 2-36

Coordinates: (11.36°, 36.35°)
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The faint rusty red glow of nearby giant molecular cloud MBM 39.

You can view a more detailed image of this nebula here.

Sh 2-37

Coordinates: (11.63°, -1.78°)
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Sh 2-37 lies in the direction of the ionising star cluster Dias 5. It is also known as IC 1283/1284 and the powerful radio source W 34.

Sh 2-35 and Sh 2-37 are associated with a 130 thousand solar mass giant molecular cloud and appear to be part of the Sgr OB7 association. Sh 2-37 is visible through a hole in this molecular cloud. This is a very active star formation region.

You can find an infrared image of part of this region here, full colour images here and here, and an analysis of the correct names for these objects here.

Sh 2-38

Coordinates: (11.89°, 0.79°)
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Sh 2-38 is a tiny nebula that lies in the direction of the edge of the Sgr OB1 association. It has no significant references in the scientific literature and no ionising stars are known in this direction.

An obvious bubble appears in this direction in this Spitzer infrared image. It is catalogued as bubble [CPA2006] N4.

Sh 2-39

Coordinates: (12.4°, -1.1°)
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Sh 2-39 is a tiny nebula contained within the boundaries of the much larger Sh 2-41 in the direction of the Sgr OB4 association. There is a bubble in this direction in the MSX infrared data.

Avedisova concludes that Sh 2-39 is ionised by the B1 III giant HD 167611 and the B2 III giant BD -18 4892 (HD 313050), at a distance of 2670 +/- 150 parsecs. She places the nebula in star formation region 12.46-1.07 along with a water maser and the young stellar object IRAS 18139-1842.

Sh 2-40

Coordinates: (12.72°, 0.35°)
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Sh 2-40 appears as several bright knots of nebulosity extending above the much larger nebula Sh 2-41.

Avedisova suggests that Sh 2-40 is ionised by the B-class star LSS 4756.

The RCW catalog lists the bit of Sh 2-40 that is furthest from the galactic plane as RCW 155a and the brighter bits closer to the galactic plane as RCW 155b.

Navigate to nebula [ Previous | Next ]

Stewart Sharpless published the second and final version of his famous nebula catalog in 1959. Although astronomers publish articles referring to the Sharpless nebulae almost every month, there seems to be few places on the Internet that bring together information on these nebulae as a whole - unlike, for example, the Messier catalog. This is most likely because the Messier objects are visible to anyone with a pair of binoculars or a small telescope. Most of the Sharpless objects are clearly visible only in CCD images or in photographic plates taken by large telescopes. Fortunately some of these plates have now been digitally scanned and made publicly available.

Many of the brightest and most beautiful Milky Way star formation regions visible from the northern hemisphere are in the Sharpless catalog so the 313 objects it contains are well worth examining carefully. (In fact there are more than 313 objects as subsequent research has shown that some of the Sharpless nebulae consist of more than one object.) Although the Sharpless catalog is only intended to be complete for objects visible north of declination -27 degrees, a similar catalog covering the southern hemisphere was published by Alex Rodgers, Colin Campbell, and John Whiteoak in 1960, which is largely an expansion of Colin Gum's earlier catalog. You can visit a gallery of these RCW nebulae here. At least 50 objects in the Sharpless catalog are also in the RCW catalog and I have noted this in the descriptions of these objects.

Most of the images used to illustrate the Sharpless catalog were created using the POSS-II/UKSTU data of the Digitized Sky Survey, or, where available, the more detailed SuperCOSMOS Sky Survey. In both cases, green = UKST Infrared. Because green represents infrared, the images are not quite the same as would be seen at purely visual frequencies. Green in these images usually reveals warm dust or red giant stars.

These images were created using the POSS-II/UKSTU data of the Digitized Sky Survey and SuperCOSMOS using the process described here.

According to my correspondence with the Royal Observatory Edinburgh and the Space Telescope Science Institute, I am allowed to use the POSS-II/UKSTU data to create and display images for non-commercial purposes so long as I include this fine print for the SuperCOSMOS data:

Use of these images is courtesy of the UK Schmidt Telescope (copyright in which is owned by the Particle Physics and Astronomy Research Council of the UK and the Anglo-Australian Telescope Board) and the Southern Sky Survey as created by the SuperCOSMOS measuring machine and are reproduced here with permission from the Royal Observatory Edinburgh.

and this acknowledgement taken from the DSS site:

The Digitized Sky Surveys were produced at the Space Telescope Science Institute under U.S. Government grant NAG W-2166. The images of these surveys are based on photographic data obtained using the Oschin Schmidt Telescope on Palomar Mountain and the UK Schmidt Telescope. The plates were processed into the present compressed digital form with the permission of these institutions.

The Second Palomar Observatory Sky Survey (POSS-II) was made by the California Institute of Technology with funds from the National Science Foundation, the National Geographic Society, the Sloan Foundation, the Samuel Oschin Foundation, and the Eastman Kodak Corporation.

The UK Schmidt Telescope was operated by the Royal Observatory Edinburgh, with funding from the UK Science and Engineering Research Council (later the UK Particle Physics and Astronomy Research Council), until 1988 June, and thereafter by the Anglo-Australian Observatory. The blue plates of the southern Sky Atlas and its Equatorial Extension (together known as the SERC-J), as well as the Equatorial Red (ER), and the Second Epoch [red] Survey (SES) were all taken with the UK Schmidt.

The "Second Epoch Survey" of the southern sky was made by the Anglo-Australian Observatory (AAO) with the UK Schmidt Telescope. Plates from this survey have been digitized and compressed by the ST ScI. The digitized images are copyright © 1993-5 by the Anglo-Australian Observatory Board, and are distributed herein by agreement.

The "Equatorial Red Atlas" of the southern sky was made with the UK Schmidt Telescope. Plates from this survey have been digitized and compressed by the ST ScI. The digitized images are copyright © 1992-5, jointly by the UK SERC/PPARC (Particle Physics and Astronomy Research Council, formerly Science and Engineering Research Council) and the Anglo-Australian Telescope Board, and are distributed herein by agreement.

The compressed files of the "Palomar Observatory - Space Telescope Science Institute Digital Sky Survey" of the northern sky, based on scans of the Second Palomar Sky Survey are copyright © 1993-1995 by the California Institute of Technology and are distributed herein by agreement. The compressed files of the "Palomar Observatory - Space Telescope Science Institute Digital Sky Survey" of the northern sky, based on scans of the Second Palomar Sky Survey are copyright © 1993-1995 by the California Institute of Technology and are distributed herein by agreement.