| Discovery[1] | |
|---|---|
| Discovered by | A. Schwassmann |
| Discovery site | Bergedorf Obs. |
| Discovery date | 16 March 1928 |
| Designations | |
| (1303) Luthera | |
Named after | Robert Luther[2] (German astronomer) |
| 1928 FP · 1926 XD 1928 HH · 1972 VP1 A917 KC | |
| main-belt · (outer)[1][3] Luthera[4] | |
| Orbital characteristics[1] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 89.60 yr (32,726 days) |
| Aphelion | 3.5680AU |
| Perihelion | 2.8910 AU |
| 3.2295 AU | |
| Eccentricity | 0.1048 |
| 5.80yr (2,120 days) | |
| 198.00° | |
| 0° 10m 11.28s / day | |
| Inclination | 19.491° |
| 72.049° | |
| 100.43° | |
| Physical characteristics | |
| Dimensions | 81.685±0.494 km[5] 85.08 km(derived)[3] 87.15±1.13 km[6] 90.65±25.04 km[7] 91.35±24.52 km[8] 92.118±2.084 km[9] 112.74±1.41 km[10] |
| 5.878±0.003h[11] 7.92±0.05 h[12] | |
| 0.024±0.003[10] 0.0387(derived)[3] 0.04±0.02[8] 0.04±0.03[7] 0.0523±0.0093[9] 0.059±0.002[6] | |
| C[3] | |
| 9.00[6][9] · 9.40[7][10] · 9.5[1][3] · 9.51[8] | |
1303 Luthera, provisional designation1928 FP, is a darkasteroid and the parent body of theLuthera family, located in the outermost regions of theasteroid belt. It measures approximately 90 kilometers in diameter. The asteroid was discovered on 16 March 1928, by astronomerFriedrich Schwassmann at theBergedorf Observatory in Hamburg, Germany, and later named after German astronomerRobert Luther.[2][13]
Luthera is theparent body of theLuthera family (904), a smallerasteroid family of less than 200 known members.[4][14]: 23 It orbits the Sun in theoutermost asteroid belt at a distance of 2.9–3.6 AU once every 5 years and 10 months (2,120 days;semi-major axis of 3.23 AU). Its orbit has aneccentricity of 0.10 and aninclination of 19° with respect to theecliptic.[1]
The asteroid was first observed asA917 KC atSimeiz Observatory in May 2017. The body'sobservation arc begins atHeidelberg Observatory in April 1928, or one month after its official discovery observation at Bergedorf.[13]
Due to its lowgeometric albedo,Luthera is an assumed carbonaceousC-type asteroid,[3] while the overallspectral type for members of theLuthera family is that of anX-type.[14]: 23
In February 2008, a rotationallightcurve ofLuthera was obtained from photometric observations by Mexican astronomerPedro Sada at theUniversity of Monterrey, Mexico. Lightcurve analysis gave a shortrotation period of 5.878 hours with a low brightness variation of 0.05magnitude, indicative for a nearly spherical shape (U=3).[11] A lower-rated lightcurve with a period of 7.92 hours and an amplitude of 0.06 magnitude was obtained by French amateur astronomerPierre Antonini in May 2009 (U=2).[12]
According to the surveys carried out by the JapaneseAkari satellite and theNEOWISE mission of NASA'sWide-field Infrared Survey Explorer,Luthera measures between 81.685 and 112.74 kilometers in diameter and its surface has a lowalbedo between 0.024 and 0.059.[5][6][7][8][9][10]
TheCollaborative Asteroid Lightcurve Link derives an albedo of 0.0387 and a diameter of 85.08 kilometers based on anabsolute magnitude of 9.5.[3]
Thisminor planet was named after German astronomerKarl Theodor Robert Luther (1822–1900), who was adiscoverer of minor planets himself, most notably17 Thetis,90 Antiope (binary) and288 Glauke (slow rotator). The official naming citation was mentioned inThe Names of the Minor Planets byPaul Herget in 1955 (H 119). The lunar craterLuther has also been named after him.[2]
