| Discovery[1] | |
|---|---|
| Discovered by | M. F. Wolf |
| Discovery site | Heidelberg Obs. |
| Discovery date | 25 February 1917 |
| Designations | |
| (866) Fatme | |
Named after | Fatme, a character in the operaAbu Hassan (Carl Maria von Weber)[2] |
| A917 DG · 1950 DF1 1917 BQ | |
| main-belt[1][3] · (outer) background[4][5] | |
| Orbital characteristics[3] | |
| Epoch 31 May 2020 (JD 2459000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 102.93yr (37,596 d) |
| Aphelion | 3.2871AU |
| Perihelion | 2.9606 AU |
| 3.1238 AU | |
| Eccentricity | 0.0523 |
| 5.52 yr (2,017 d) | |
| 34.544° | |
| 0° 10m 42.6s / day | |
| Inclination | 8.6616° |
| 91.060° | |
| 263.20° | |
| Physical characteristics | |
| 5.800±0.002 h[10] | |
| SMASS =X[3] | |
| 9.50[1][3] | |
866 Fatme (prov. designation:A917 DGor1917 BQ) is a largebackground asteroid, approximately 86 kilometers (53 miles) in diameter, located in the outer region of theasteroid belt. It was discovered by German astronomerMax Wolf at theHeidelberg-Königstuhl State Observatory on 25 February 1917.[1] TheX-type asteroid has a shortrotation period of 5.8 hours. It was named after "Fatme", a character in the operaAbu Hassan byCarl Maria von Weber (1786–1826).[2]
Fatme is a non-family asteroid of the main belt'sbackground population when applying thehierarchical clustering method to itsproper orbital elements.[4][5] It orbits the Sun in theouter asteroid belt at a distance of 3.0–3.3 AU once every 5 years and 6 months (2,017 days;semi-major axis of 3.12 AU). Its orbit has aneccentricity of 0.05 and aninclination of 9° with respect to theecliptic.[3] The body'sobservation arc begins atHeidelberg Observatory on 16 March 1917, or three weeks after its official discovery observation.[1]
Thisminor planet was named after Fatme, a character in the operaAbu Hassan by German composerCarl Maria von Weber (1786–1826). The officialnaming was also mentioned inThe Names of the Minor Planets byPaul Herget in 1955 (H 85).[2] Another asteroid865 Zubaida, was also named after a character of this opera. The composer himself was honored with the naming of4152 Weber.
In the Bus–BinzelSMASS classification,Fatme is anX-type asteroid.[3]
In June 2018, a rotationallightcurve ofFatme was obtained from 5 nights ofphotometric observations byTom Polakis at the Command Module Observatory (V02) in Arizona. Lightcurve analysis gave arotation period of5.800±0.002 hours with a brightness variation of0.21±0.02magnitude (U=2).[10] The result supersedes previously reported period determinations of20.03±0.01 hours with an amplitude of0.21±0.05 magnitude byRobert Stephens at the Santana Observatory (646), California, in May 2001 (U=2),[11]9.4±0.2 hours with an amplitude of0.06±0.01 magnitude (tentative) by French amateur astronomerLaurent Bernasconi in December 2004 (U=1),[12]9.36±0.05 hours with an amplitude of0.06±0.01 magnitude (tentative) by French amateur astronomerRené Roy in May 2012 (U=2−),[12] and20.7±0.1 hours with an amplitude of0.12±0.02 magnitude by the Spanish group of asteroid observers, OBAS, in January 2016 (U=2−).[13]
According to the surveys carried out by theNEOWISE mission of NASA'sWide-field Infrared Survey Explorer (WISE), the JapaneseAkari satellite, and the Infrared Astronomical SatelliteIRAS,Fatme measures (78.061±0.360), (86.49±1.16) and (88.31±2.0) kilometers in diameter and its surface has analbedo of (0.046±0.007), (0.038±0.001) and (0.0473±0.002), respectively.[6][7][9][8] TheCollaborative Asteroid Lightcurve Link derives an albedo of 0.0361 and a diameter of 88.11 kilometers based on anabsolute magnitude of 9.5.[14] Alternative mean-diameter measurements published by the WISE team include (82.388±1.055 km), (88.25±26.33 km) and (95.83±37.32 km) with corresponding albedos of (0.0412±0.0096), (0.04±0.03) and (0.03±0.02).[5][14]
