_La_Plata.png) Shape model ofLa Plata from itslightcurve | |
| Discovery[1] | |
|---|---|
| Discovered by | J. F. Hartmann |
| Discovery site | La Plata Obs. |
| Discovery date | 28 April 1924 |
| Designations | |
| (1029) La Plata | |
Named after | La Plata[2](city in Argentina and discovering observatory) |
| 1924 RK · 1938 DR2 1969 OU · A916 UL A916 UR | |
| main-belt[1][3] · (outer) Koronis[4][5] | |
| Orbital characteristics[3] | |
| Epoch 23 March 2018 (JD 2458200.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 100.68yr (36,772 d) |
| Aphelion | 2.9715AU |
| Perihelion | 2.8083 AU |
| 2.8899 AU | |
| Eccentricity | 0.0282 |
| 4.91 yr (1,794 d) | |
| 87.729° | |
| 0° 12m 2.16s / day | |
| Inclination | 2.4254° |
| 29.903° | |
| 142.56° | |
| Physical characteristics | |
| 16.46±1.07 km[6] 19.32±2.72 km[7] 20.71 km(derived)[4] 20.78±1.9 km[8] | |
| 14 h[9] 14.174±0.003 h[10] 15.310±0.003 h[11] 15.37 h[12] | |
| 0.1655(derived)[4] 0.1819±0.039[8] 0.229±0.246[7] 0.310±0.045[6] | |
| Tholen =S[3][4] · S[13] B–V = 0.787[3] U–B = 0.390[3] | |
| 10.79[7] · 10.88[3][6][8] 10.99[4][12] 11.01±0.01[11] 11.37±0.60[13] | |
1029 La Plata, provisional designation1924 RK, is a stonyKoronis asteroid from the outer regions of theasteroid belt, approximately 20 kilometers (12 miles) in diameter. It was discovered on 28 April 1924, by German astronomerJohannes Hartmann at theLa Plata Astronomical Observatory in Argentina.[1] It was named after the city ofLa Plata, Argentina, where the discovering observatory is located. The possibly elongatedS-type asteroid has arotation period of 15.31 hours.[3]
La Plata is a member of theKoronis family (605),[4][5] a prominentasteroid family with nearly co-planarecliptical orbits and one of thelargest families in the main belt at all.[14] It orbits the Sun in theouter asteroid belt at a distance of 2.8–3.0 AU once every 4 years and 11 months (1,794 days;semi-major axis of 2.89 AU), which is near the 5:2resonance with Jupiter (2.82 AU). Its orbit has aneccentricity of 0.03 and aninclination of 2° with respect to the ecliptic.[3]
The asteroid was first observed asA916 UL andA916 UR at the observatories atSimeiz andAlgiers in October 1916, respectively. Itsobservation arc begins with the latter observation at Algiers on 31 October 1916, more than 7 years prior its official discovery observation at La Plata.[1]
In theTholen classification,La Plata is a common, stonyS-type asteroid,[3][4] which agrees with the overallspectral type for Koronian asteroids.[14]: 23 Thephotometric survey conducted byPan-STARRS also characterized it as an S-type.[13]
In October 2004, a rotationallightcurve ofLa Plata was obtained from photometric observations during an extensive survey of Koronian asteroids at seven different observatories in the United States. Lightcurve analysis gave a well-definedrotation period of 15.310 hours with a brightness variation of 0.58magnitude (U=3).[11] Previous measurements from 1975 and 1983 showed a period of 14 and 15.37 hours, respectively (U=2/2).[9][12] Also in October 2004, an alternative period of 14.174 hours was obtained by French amateur astronomerLaurent Bernasconi (U=2).[10] The consolidated brightness amplitude of 0.26 to 0.58 magnitude indicates that the body's shape is somewhat elongated.[4]
According to the surveys carried out by the Infrared Astronomical SatelliteIRAS, the JapaneseAkari satellite and theNEOWISE mission of NASA'sWide-field Infrared Survey Explorer,La Plata measures between 16.46 and 20.78 kilometers in diameter and its surface has analbedo between 0.1819 and 0.310.[6][7][8] TheCollaborative Asteroid Lightcurve Link derives an albedo of 0.1655 and a diameter of 20.71 kilometers based on anabsolute magnitude of 10.99.[4]
Thisminor planet was named after the city ofLa Plata, Argentina, where the discoveringLa Plata Astronomical Observatory is located. The official naming citation was mentioned inThe Names of the Minor Planets byPaul Herget in 1955 (H 98).[2]
