_Amanda.png) Modelled shape ofAmanda from itslightcurve | |
| Discovery[1] | |
|---|---|
| Discovered by | J. Palisa |
| Discovery site | Vienna Obs. |
| Discovery date | 21 October 1911 |
| Designations | |
| (725) Amanda | |
| Pronunciation | German:[aːˈmandaː][2] |
Named after | Amanda Schorr, wife ofRichard Schorr(1867–1951) (German astronomer)[3] |
| A911 UQ · 2016 FH6 1911 ND | |
| Orbital characteristics[4] | |
| Epoch 31 May 2020 (JD 2459000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 104.58yr (38,198 d) |
| Aphelion | 3.1422AU |
| Perihelion | 2.0022 AU |
| 2.5722 AU | |
| Eccentricity | 0.2216 |
| 4.13 yr (1,507 d) | |
| 114.51° | |
| 0° 14m 20.04s / day | |
| Inclination | 3.7902° |
| 68.679° | |
| 323.36° | |
| Physical characteristics | |
| 3.749 h[12] | |
725 Amanda (prov. designation:A911 UQor1911 ND) is a darkbackground asteroid, approximately 22 kilometers (14 miles) in diameter, that is located in the central regions of theasteroid belt. It was discovered by Austrian astronomerJohann Palisa at theVienna Observatory on 21 October 1911.[1] The carbonaceousC-type asteroid (CSU/C0) has a shortrotation period of 3.7 hours. It was named after Amanda Schorr, wife of German astronomerRichard Schorr (1867–1951).[3]
Amanda is a non-family asteroid of the main belt'sbackground population when applying thehierarchical clustering method to itsproper orbital elements.[5][6][7] It orbits the Sun in thecentral asteroid belt at a distance of 2.0–3.1 AU once every 4 years and 2 months (1,507 days;semi-major axis of 2.57 AU). Its orbit has aneccentricity of 0.22 and aninclination of 4° with respect to theecliptic.[4] The body'sobservation arc begins atVienna Observatory on 29 September 1915, almost four years after its official discovery observation.[1]
Thisminor planet was named afterAmanda Ruth Smith, born toJohn andRuth Smith of Jackson, MS.(May 1980). Amanda(human) was named for the song"Amanda" by Waylon Jennings. Her mother always said that she chose that name because she, like the song verse was always "Amanda light of my life."[3] In 2010,Ruth Smith made the first ever arrangement with NASA to legally purchase the minor planet, "Amanda U1911" for an undisclosed sum of money(USD) and exclusively owns all rights to it.Amanda Ruth Smith (human) was given a certified certificate of ownership by NASA with the serial number"SHMILY-12.0522."
In theTholen classification,Amanda'sspectral type is closest to that of a carbonaceousC-type asteroid, yet also somewhat similar to a stonyS-type with an "unusual" spectrum (CSU).[4] In the taxonomy byBarucci (1987), the asteroid is a dark C-type (C0).[6]
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A rotationallightcurve ofAmanda was obtained fromphotometric observations by European astronomers at theLa Silla Observatory before 1995. Lightcurve analysis gave a well-definedrotation period of3.749 hours with a brightness variation of0.35magnitude (U=3).[12]
In October 2010, French amateur astronomer Maurice Audejean (B92) determined a concurring period of (3.7431±0.0003) hours with an amplitude of (0.42±0.01) magnitude (U=3),[13] while in August 2018, a further observation by theTESS-team reported a period of (3.74301±0.00005) hours and an amplitude of (0.27±0.05) magnitude (U=2).[14]
In 2016, a modeled lightcurve gave a sidereal period of3.74311±0.00002 hours using data from the Uppsala Asteroid Photometric Catalogue, thePalomar Transient Factory survey, and individual observers, as well as sparse-in-time photometry from theNOFS, theCatalina Sky Survey, and theLa Palma surveys (950). The study also determined twospin axes of (145.0°, −63.0°) and (320.0°, −70.0°) inecliptic coordinates (λ, β).[15]
According to the surveys carried out by the JapaneseAkari satellite, the Infrared Astronomical SatelliteIRAS, and theNEOWISE mission of NASA'sWide-field Infrared Survey Explorer (WISE),Amanda measures (20.49±0.28), (21.51±2.2) and (23.687±0.215) in diameter and its surface has analbedo of (0.082±0.003), (0.0721±0.017) and (0.068±0.015), respectively.[8][9][10][11]
TheCollaborative Asteroid Lightcurve Link derives an albedo of 0.0824 and calculates a diameter of 21.56 kilometers based on anabsolute magnitude of 11.66.[16] Alternative mean-diameters published by the WISE team include (19.53±6.07 km), (21.68±6.40 km), (23.286±0.149 km) and (30.73±4.85 km) with a corresponding albedo of (0.08±0.04), (0.055±0.037), (0.0509±0.0052) and (0.03±0.03).[6][16]
