Sh 2-37

Sh 2-37, also known by the designation IC 1284, or the common name Twiddlebug Nebula,^[5] is an emission nebula in the constellation Sagittarius. It is located is the direction of ionizing star cluster Dias 5. It also contains the radio source W 34.^[6]

Sharpless 2-37

Emission nebula
H II region
As viewed in 2023
Observation data: epoch
Right ascension	18h 18m 48s
Declination	−19° 45′ 03″[1]
Distance	5800[2] ly
Apparent magnitude (V)	7.7[3]
Apparent dimensions (V)	19.2' × 14.2'
Constellation	Sagittarius
Physical characteristics
Radius	34[4] ly
Designations	Gum 78, IC 1283/4, RCW 153, LBN 47
See also: Lists of nebulae

It is located near the center of the galaxy, and is partially obscured by dust. Nearby Sh 2-37, which appears mostly red, are two small blue reflection nebulae, known as NGC 6589 and NGC 6590.^[7][8] SIMBAD notably provides the wrong coordinates for Sh 2-37, giving it the same coordinates as nearby NGC 6590.^[9]

Discovery

Sh 2-37 was discovered by Edward Emerson Barnard on a photographic plate on 31 May 1892. He initially described it as a 'nebulous star'.^[10]