Robin's Egg Nebula (NGC 1360)
History
The planetary nebula was discovered by the American astronomer Lewis Swift in 1859 using his private 4.5 inch refractor. [277] Swift did not publish his observation until 1885, that's why the PN was independently discovered by Wilhelm Tempel on 9 October 1861, by August Winnecke in January 1868 and by Eugen Block on 18 October 1878. [196] John L. E. Dreyer listed the planetary nebula as NGC 1360 and added the description: «Star of 8th magnitude in bright, large nebula, elongated north-south.» [313]
Physical Properties
NGC 1360 is a large and evolved planetary nebula without an obvious shell morphology. It is thought to be a prolate ellipsoidal shell with the major axis twice as long and it is tilted by 60° towards the line of sight. A Gaussian radial density profile without a sharp inner edge indicates a lack of compression by stellar wind. The kinematic age is around 10'000 years. The low density of ≤ 130 H atom cm-3 implies that it has begun to merge with the interstellar medium. The regions with low-ionization emission near the end of the major axis expand faster than the shell. They are younger than the nebular shell. [539]
| Designation | NGC 1360 |
| Type | PN |
| Right Ascension (J2000.0) | 03h 33m 14.6s |
| Declination (J2000.0) | -25° 52' 16" |
| Diameter | 6.42 arcmin |
| Photographic (blue) magnitude | 9.6 mag |
| Visual magnitude | 9.4 mag |
| Metric Distance | 0.392 kpc |
| Dreyer Description | * 8 in B, L neb, E ns |
| Identification, Remarks | GC 5315; PK 220-53.1; ESO 482-PN7; AM 0331-260; CS=11.4 |
Finder Chart
The planetary nebula NGC 1360 is located in the constellation Fornax at a declination of -35° and is thus low in the southern sky. The best time for this is around November, when the constellation is highest above the southern horizon at midnight. Follow the Eridanus next to Rigel in the constellation Orion starting at the second bend of the river. Unless the three stars Dalim (α Fornacis, 3.79 mag) — β Fornacis (4.46 mag) — ν Fornacis (4.96 mag) sink into Milano's dome of light or are blocked by a mountain, they point the way to NGC 1360. The PN is located in the prolongation of β to α Fornacis, about 0.5° south of two 6th magnitude stars.
