_Shajna.png) Shape model ofShajna from itslightcurve | |
| Discovery[1] | |
|---|---|
| Discovered by | P. Shajn |
| Discovery site | Simeiz Obs. |
| Discovery date | 5 September 1935 |
| Designations | |
| (1648) Shajna | |
Named after | Couple of astronomers (Pelageya andGrigory)[2] |
| 1935 RF · 1934 CK1 1938 MC · 1941 FD 1948 LC · 1951 EX2 1952 SX · 1952 UW 1955 QT · 1955 RP A921 GB · A924 EQ | |
| main-belt · (inner)[3] | |
| Orbital characteristics[1] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 95.99 yr (35,061 days) |
| Aphelion | 2.6971AU |
| Perihelion | 1.7737 AU |
| 2.2354 AU | |
| Eccentricity | 0.2065 |
| 3.34yr (1,221 days) | |
| 250.93° | |
| 0° 17m 41.64s / day | |
| Inclination | 4.5723° |
| 130.42° | |
| 134.71° | |
| Physical characteristics | |
| Dimensions | 8.26±1.47 km[4] 8.30±0.30 km[5] 9.23 km(calculated)[3] 9.450±0.141 km[6][7] |
| 6.41368±0.00001h[8] 6.41369±0.00005 h[9] 6.4140±0.0002 h[10] 6.4140±0.0164 h(R)[11] 6.4248±0.0164 h(S)[11] | |
| 0.191±0.016[6][7] 0.20(assumed)[3] 0.247±0.049[5] 0.35±0.13[4] | |
| Tholen =S[1] · S[3] B–V = 0.792[1] U–B = 0.497[1] | |
| 11.838±0.003(R)[11] · 12.21[4] · 12.54[1][3][5][6] | |
1648 Shajna, provisional designation1935 RF, is a stonyasteroid from the inner regions of theasteroid belt, approximately 9 kilometers in diameter. It was discovered on 5 September 1935, by Russian astronomerPelageya Shajn atSimeiz Observatory on the Crimean peninsula.[12] Two weeks later, it was independently discovered byCyril Jackson atJohannesburg Observatory, South Africa. It was later named after the discoverer and her husband, Russian astronomersGrigory Shajn.[2]
Shajna orbits the Sun in theinner main-belt at a distance of 1.8–2.7 AU once every 3 years and 4 months (1,221 days). Itswell-determined orbit has aneccentricity of 0.21 and aninclination of 5° with respect to theecliptic.[1] In 1921,Shajna was first identified as1921 GB atHeidelberg Observatory. Its first used observation was taken atUccle in 1934, when it was identified as1934 CK1, extending the body'sobservation arc by one year prior to its official discovery observation.[12]
In July 2005, a rotationallightcurve of was obtained by French amateur astronomerLaurent Bernasconi. It gave a well-definedrotation period of 6.4140 hours with a brightness variation of 0.65magnitude (U=3).[10] Two modeled lightcurves from various surveys including the Lowell photometric database gave similar periods of 6.41368 and 6.41369 hours (U=n.a.).[8][9] Photometric observations at thePalomar Transient Factory in September 2012, gave nearly identical periods of 6.4140 and 6.4248 hours in the R- and S-band, respectively (U=2/2).[11]
According to the surveys carried out by NASA'sWide-field Infrared Survey Explorer with its subsequentNEOWISE mission,Shajna measures between 8.26 and 9.45 kilometers in diameter, and its surface has analbedo between 0.191 and 0.35.[4][5][6][7] TheCollaborative Asteroid Lightcurve Link assumes a standard albedo for stony asteroids of 0.20 and calculates a diameter of 9.23 kilometers with anabsolute magnitude of 12.54.[3]
Thisminor planet was named in honor of the late couple of Russian astronomersGrigory Shajn (1892–1956) and the discoverer herself,Pelageya Shajn (1894–1956), first woman ever to discover a minor planet. The asteroid1190 Pelagia is also named after her, while her husband is honored by the lunar craterShayn.[2] The officialnaming citation was published by theMinor Planet Center on 20 February 1962 (M.P.C. 2117).[13]
