| Discovery[1] | |
|---|---|
| Discovered by | K. Reinmuth |
| Discovery site | Heidelberg Obs. |
| Discovery date | 31 August 1927 |
| Designations | |
| (1085) Amaryllis | |
| Pronunciation | /æməˈrɪlɪs/[2] |
Named after | Amaryllis[3] (flowering plant) |
| 1927 QH · 1964 CL A908 HB · A915 QA A921 RC | |
| main-belt · (outer)[4] background[5] | |
| Orbital characteristics[1] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 109.40 yr (39,957 days) |
| Aphelion | 3.3182AU |
| Perihelion | 3.0506 AU |
| 3.1844 AU | |
| Eccentricity | 0.0420 |
| 5.68yr (2,076 days) | |
| 40.309° | |
| 0° 10m 24.24s / day | |
| Inclination | 6.6396° |
| 139.98° | |
| 127.53° | |
| Physical characteristics | |
| Dimensions | 65.55±14.66 km[6] 67.14±21.21 km[7] 69.281±0.124 km[8] 69.68 km(derived)[4] 69.95±1.4 km[9] 71.025±1.105 km[10] 72.93±0.78 km[11] |
| 18.111±0.025h[12] 18.2±0.1 h[13] | |
| 0.04±0.02[6] 0.04±0.04[7] 0.0437(derived)[4] 0.058±0.002[11] 0.0608±0.0058[10] 0.0628±0.003[9] 0.067±0.013[8] | |
| X[14] · C(assumed)[4] | |
| 9.40[9][10][11] · 9.70[6] · 9.8[1][4] · 9.81[7] · 9.92±0.25[14] | |
1085 Amaryllis/æməˈrɪlɪs/, provisional designation1927 QH, is a backgroundasteroid from the outer regions of theasteroid belt, approximately 69 kilometers in diameter. It was discovered on 31 August 1927, by astronomerKarl Reinmuth at theHeidelberg-Königstuhl State Observatory in southwest Germany.[15] The asteroid was named after the flowering plantAmaryllis.[3]
Amaryllis is a non-family asteroid from the main belt'sbackground population.[5] It orbits the Sun in theouter asteroid belt at a distance of 3.1–3.3 AU once every 5 years and 8 months (2,076 days). Its orbit has aneccentricity of 0.04 and aninclination of 7° with respect to theecliptic.[1]
The asteroid was first identified asA908 HB at Taunton Observatory (803) in April 1908. A few days later, the body'sobservation arc begins at theUnited States Naval Observatory (786) in May 1908, or more than 19 years prior to its official discovery observation at Heidelberg.[15]
Amaryllis has been characterized as anX-type asteroid byPan-STARRS photometric survey.[14] It is also an assumed carbonaceousC-type asteroid.[4]
In March 2004, a first rotationallightcurve ofAmaryllis was obtained from photometric observations by French amateur astronomerRené Roy. Lightcurve analysis gave arotation period of 18.2 hours with a brightness variation of 0.20magnitude (U=2).[13] In May 2016, the Spanish amateur astronomer group OBAS (Asteroid Observers,Spanish:Observadores de Asteroids) measured a refined period of 18.111 hours with an amplitude of 0.19 magnitude (U=3-).[12]
According to the surveys carried out by the Infrared Astronomical SatelliteIRAS, the JapaneseAkari satellite and theNEOWISE mission of NASA'sWide-field Infrared Survey Explorer,Amaryllis measures between 65.55 and 72.93 kilometers in diameter and its surface has analbedo between 0.04 and 0.067.[6][7][8][9][10][11]
TheCollaborative Asteroid Lightcurve Link derives an albedo of 0.0437 and a diameter of 69.68 kilometers based on anabsolute magnitude of 9.8.[4]
Thisminor planet was named after the flowering planetAmaryllis, also known as belladonna lily, Jersey lily, naked lady, or amarillo. The official naming citation was mentioned inThe Names of the Minor Planets byPaul Herget in 1955 (H 102).[3]
Due to his many discoveries,Karl Reinmuth submitted a large list of 66 newly named asteroids in the early 1930s. The list covered his discoveries with numbers between(1009) and(1200) and also contained a sequence of 28 asteroids, starting with1054 Forsytia, that were named after plants, in particularflowering plants(also seelist of minor planets named after animals and plants § Plants).[16]