M17 - NGC 6618
DSS image of M17
Overlaid DSS image of M17, 120' x 120' with north at top and west to the right

Aladin viewer for the region around M17
Swan Nebula, Omega Nebula, Horseshoe Nebula, Lobster Nebula, Checkmark Nebula
Bode 54, h 2008, GC 4403, Collinder 337, Cr 377, Sh2-45, Lund 827, LBN 60, OCl 44

Magnitude  6
Size  46'
Right Ascension  18h 20' 47.0"  (2000)
Declination  16° 10' 17" S
Constellation  Sagittarius
Description  !!!, B, eL, eiF, 2 hooked
Classification  III 3 m
Observing Notes

Andrew Cooper
Jun 27, 2020    Waikoloa Quarry, HI (map)
8x42mm Nikon Prostaff 3S Binoculars @ 8x

A bright conspicuous object just north of M24, a couple degrees off the north end of the star cloud, nebulous and sprinkled with faint stars, 15' in diameter, M16 visible 2.5° further north

Andrew Cooper
Jun 29, 2019    Kaʻohe, Mauna Kea, HI (map)
20cm f/6 Newtonian, Cave Astrola @ 56x

Large, bright, a bright nebulae with a modest cluster of stars involved, with the Newtonian the swan is upright making the name obvious, a brighter central region is surrounded by extensive faint nebulosity and a very rich galactic star field

Andrew Cooper
Aug 12, 2017    Waikoloa, HI (map)
Hodgepodge w/TV-76mm f/6 APO @ 30x

A bright patch of nebulae in a dense starfield, bright with an even brighter central region composing the namesake swan, about 10' across, much of the fainter surrounding nebulosity not visible with the 76mm, the entire field is mottled with dark nebulae

Andrew Cooper
May 30, 2017    Hale Pohaku, HI (map)
46cm f/4.5 Newtonian, Deep Violet @ 175x

A beautiful object, rich nebulosity fills the entire ½° field, the central region is quite bright, distinct from the surrounding region of fainter nebulosity, about 15'x7' longer in the east-west direction, this central core very much resembles a swimming swan seen in profile thus the common name, addition of an O-III or nebula band filter reveals exceptional mottling in this central region, also enhancing the surrounding field of fainter nebulae

Andrew Cooper
Apr 19, 2012    Hale Pohaku, HI (map)
46cm f/4.5 Newtonian, Deep Violet @ 175x

A beautiful region of rich starfield laced with nebulae, the main body of M17 is quite bright, about 15' in diamter and really does resemble the swimming swan of its namesake, the effect is enhanced by regions of dark nebulae surrounding the brighter central region

Andrew Cooper
Apr 18, 2010    Hale Pohaku, HI (map)
46cm f/4.5 Newtonian, Deep Violet @ 175x

Large! Bright! fills the ½° field of the 12mmNagIV, the main body has extensive mottling with a sharply defined west side dropping into a dark background, on the east side the nebula gradually fades for at least 1°, rich starfield throughout the entire region

Andrew Cooper
May 25, 1998    Picacho Peak State Park, AZ (map)
20cm f/10 SCT

Not hard to see why it is called the swan, clear definition to the brighter nebular regions

Rev. T.W. Webb
May 19, 1885    Hardwick, Herefordshire, England (map)

The 'horseshoe' neb. visible in finder, 1° n of M18, described by Sm. as a magnificent, arched, and irresolvable nebulosity-- in a splendid group of stars. Well has he observed, 'The wonderful quantity of suns profusely scattered about here would be confounding, but for their increasing our reverence to the Omnipotent Creator, by revealing to us the immensity of creation.' The neb., however, Huggins finds to be gaseous; and Holden traces some changes of position with regard to the neighbouring stars.
― Celestial Objects for Common Telescopes, T. W. Webb, 1917

William Herschel
Jun 22, 1784    19 New King Street, Bath (map)

A wonderful nebula. Very much extended, with a hook on the preceding side; the nebulosity of the milky kind; several stars visible in it, but they seem to have no connection with the nebula, which is far more distant. I saw it only through short intervals of flying clouds and haziness; but the extent of the light including the hook is above 10'. I suspect besides, that on the following side it goes on much farther and diffuses itself towards the north and south. It is not of equal brightness throughout and has one or more places where the milky nebulosity seems to degenerate into the resolvable kind; such a one is that just following the hook towards the north. Should this be confirmed on a very fine night, it would bring on the step between these two nebulosities which is at present wanting, and would lead us to surmise that this nebula is a stupendous stratum of immensely distant fixed stars, some of whose branches come near enough to us to be visible as a resolvable nebulosity, while the rest runs on to so great a distance as only to appear under the milky form.

Charles Messier
Jun 3, 1764    

A train of light without stars, of 5 or 6 minutes in extent, in the shape of a spindle, & a little like that in Andromeda's belt [M31] but of a very faint light; there are two telescopic stars nearby & placed parallel to the equator. In a good sky one observes this nebula very well in an ordinary telescope of 3.5-foot. Seen again 22 March 1781.
― Connaissance des Temps, 1781
Other Data Sources for M17
Nearby objects for M17
6 objects found within 60'
FO Serpentis HD 168415 IC 4706
IC 4707 M18 NGC 6596

Drawings, descriptions, and CCD photos are copyright Andrew Cooper unless otherwise noted, no usage without permission.

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