Open Cluster NGC 2311 & H-II Region Sh 2-287
History
The open cluster was discovered by Caroline Herschel on 4 March 1783, probably with a small refractor. She enteret it as #4 in her discovery log and logged: «In the neighborhood of the 19 Monoceros, a Nebula, very obscure. Messier has it not.» [277]
William Herschel discovered it again 26 November 1786, listed it as VIII 60 and noted: «A cluster of pretty large scattered stars, not very rich. May be a projecting point of the Milky Way.» [464] Dreyer credited William Herschel as discoverer, because Caroline's observing notes never got published.
The American astronomer Stewart Sharpless searched in the 1950-ies the photo plates of the «Palomar Observatory Sky Survey» made with the 48-inch Schmidt telescope and published it in 1959 a catalogue of 313 H-II regions. He listed H-II region Sh 2-287 with 12' diameter. [310] In 1965 Beverly T. Lynds added this nebula as LBN LBN 218.08-00.35 (or LBN 1012) in her «Catalogue of Bright Nebulae». [270]
Physical Properties
| Name | Type | RA (J2000.0) | Dec (J2000.0) | PM [mas/y] | Parall. [mas] | Rvel [km/s] | z | Size ['] | Magnitudes | Identifiers |
|---|---|---|---|---|---|---|---|---|---|---|
| NGC 2311 | OpC | 06h 57m 47s | -04° 36' 48" | -1.343 | 0.462 | 100.5 | 0.000335 | 7.1 × 7.1 | V 9.6 | C 0655-045; Cl Collinder 123; NGC 2311; [FSR2007] 1127; [KPR2004b] 116; [KPS2012] MWSC 1035 |
| Sh 2-287 | HII | 06h 59m 29s | -04° 49' 12" | LBN 1012; LBN 218.08-00.35; SH 2-287; [FT96] 218.1-0.4 |
Finder Chart
The open cluster NGC 2311 and nebula Sh 2-287 can be found in the constellation Monoceros. On 4 January these are in opposition with the Sun and therefore highest in the sky at local midnight.
