| Discovery[1] | |
|---|---|
| Discovered by | K. Reinmuth |
| Discovery site | Heidelberg Obs. |
| Discovery date | 7 March 1924 |
| Designations | |
| (1020) Arcadia | |
| Pronunciation | /ɑːrˈkeɪdiə/[2] |
Named after | Arcadia(Greek region)[3] |
| 1924 QV · 1954 UA2 1975 EQ · 1977 QO2 | |
| main-belt[1][4] · (middle) Agnia[5][6] | |
| Orbital characteristics[4] | |
| Epoch 23 March 2018 (JD 2458200.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 93.89yr (34,293 d) |
| Aphelion | 2.9152AU |
| Perihelion | 2.6666 AU |
| 2.7909 AU | |
| Eccentricity | 0.0445 |
| 4.66 yr (1,703 d) | |
| 18.189° | |
| 0° 12m 41.04s / day | |
| Inclination | 4.0598° |
| 180.71° | |
| 37.691° | |
| Physical characteristics | |
| 10.067±0.090 km[7] 10.415±0.123 km[8] 13.02±0.49 km[9] 21.16 km(calculated)[10] | |
| 17.02±0.02 h[11] | |
| 0.057(assumed)[10] 0.150±0.023[9] 0.2364±0.0456[8] | |
| SMASS =S[4] · S[12] S(SDSS-MFB)[10] | |
| 12.0[4] · 12.10[8][9][10] 12.29±0.11[12] | |
1020 Arcadia, provisional designation1924 QV, is a stony Agniaasteroid from the central regions of theasteroid belt, approximately 11 kilometers (7 miles) in diameter. It was discovered on 7 March 1924, by German astronomerKarl Reinmuth at theHeidelberg Observatory in Heidelberg, Germany.[1] The asteroid was named after the Greek region ofArcadia.[3]
Arcadia is a member of theAgnia family (514),[5][6] a very largefamily of stony asteroids with more than 2000 known members.[13] They most likely formed from the breakup of abasalt object, which in turn was spawned from a largerparent body that underwentigneous differentiation.[6] The family's parent body and namesake is the asteroid847 Agnia.[13]
It orbits the Sun in thecentral main-belt at a distance of 2.7–2.9 AU once every 4 years and 8 months (1,703 days;semi-major axis of 2.79 AU). Its orbit has aneccentricity of 0.04 and aninclination of 4° with respect to theecliptic.[4] The body'sobservation arc begins at Heidelberg in March 1924, six days after its official discovery observation.[1]
In theSMASS classification,Arcadia is a common, stonyS-type asteroid.[4] It has been characterized as an S-type byPan-STARRS photometric survey,[12] as well as bySDSS-MFB (Masi Foglia Bus).[10]
In November 2011, a fragmentary rotationallightcurve ofArcadia was obtained from photometric observations by Gordon Gartrelle at theUniversity of North Dakota. Lightcurve analysis gave arotation period of 17.02 hours with a brightness amplitude of 0.05magnitude (U=1).[11] As of 2018, no secure period has been obtained.[10]
According to the survey carried out by theNEOWISE mission of NASA'sWide-field Infrared Survey Explorer,Arcadia measures between 10.067 and 13.02 kilometers in diameter and its surface has analbedo between 0.150 and 0.2364.[7][8][9] TheCollaborative Asteroid Lightcurve Link assumes an albedo 0.057, i.e. an albedo for acarbonaceous rather than for a stony asteroid, and consequently calculates a much larger diameter of 21.16 kilometers based on anabsolute magnitude of 12.1.[10] It may be speculated whether this anomaly is a glitch in the data base.
Thisminor planet was named after the Greek region ofArcadia in centralPeloponnese. It is also acelebrated mythological region, where the shepherd godPan lived. The official naming citation was mentioned inThe Names of the Minor Planets byPaul Herget in 1955 (H 97).[3]
