Little Gem Nebula (NGC 6818)
The Little Gem Nebula (NGC 6818) is a small, bright planetary nebula in the constellation Sagittarius, discovered by William Herschel in 1787. It shows two distinct layers – a spherical outer region and a brighter, vase-shaped interior bubble. A fast wind from the central star is thought to have caused the elongated shape of the inner region and also blowouts at the two ends of the major axis (top right and bottom left in the photo).
|angular diameter||22" × 15"|
|distance||~6,000 light-years (1,800 pc)|
|position||R.A. 19h 43m 57.8s,
Dec. -14° 09' 11.9"
|other designations||PK 25-17.1, GCRV 12096,
HD 186282, BD-14 5523,
PN ARO 12