| Discovery[1] | |
|---|---|
| Discovered by | J. F. Hartmann |
| Discovery site | La Plata Obs. |
| Discovery date | 4 November 1921 |
| Designations | |
| (965) Angelica | |
Named after | Angelica Hartmann (discoverer's wife)[2] |
| A921 VB · 1921 KT 1977 PM2 | |
| main-belt[1][3] · (outer) background[4][5] | |
| Orbital characteristics[3] | |
| Epoch 31 May 2020 (JD 2459000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 91.66yr (33,480 d) |
| Aphelion | 4.0444AU |
| Perihelion | 2.2703 AU |
| 3.1574 AU | |
| Eccentricity | 0.2809 |
| 5.61 yr (2,049 d) | |
| 162.59° | |
| 0° 10m 32.52s / day | |
| Inclination | 21.428° |
| 41.432° | |
| 47.020° | |
| TJupiter | 3.0400 |
| Physical characteristics | |
| 26.752±0.035 h[9][10] | |
| 10.2[1][3] | |
965 Angelica (prov. designation:A921 VBor1921 KT), is a largebackground asteroid from the outer regions of theasteroid belt, approximately 60 kilometers (37 miles) in diameter. It was discovered on 4 November 1921, by astronomerJohannes F. Hartmann at theLa Plata Astronomical Observatory in Argentina.[1] The darkX-type asteroid (Xc) with a lowTJupiter has arotation period of 26.8 hours and is likely spherical in shape. It was named after the discoverer's wife, Angelica Hartmann.[2]
Angelica 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 2.3–4.0 AU once every 5 years and 7 months (2,049 days;semi-major axis of 3.16 AU). Its orbit has aneccentricity of 0.28 and aninclination of 21° with respect to theecliptic.[3] Due to this relatively high inclination and eccentricity,Angelica has aJupiter Tisserand's parameter just barely above 3, which is commonly used as the threshold to distinguish between the populations of asteroids andJupiter-family comets. The body'sobservation arc begins atHeidelberg Observatory in December 1927, or six years after its official discovery observation at theLa Plata Astronomical Observatory.[1]
Thisminor planet was named after Angelica Hartmann, wife of German astronomerJohannes F. Hartmann, who discovered this asteroid. Thenaming was mentioned inThe Names of the Minor Planets byPaul Herget in 1955 (H 92).[2]
In the Bus–BinzelSMASS classification,Angelica is a Xc subtype, that transitions from theX-types to the carbonaceousC-type asteroids.[3][5]
During five nights in December 2017, a rotationallightcurve ofAngelica was obtained fromphotometric observations by Tom Polakis at the Command Module Observatory (V02) in Tempe, Arizona. Lightcurve analysis gave arotation period of26.752±0.035 hours with a very low brightness variation of0.08±0.01magnitude (U=3−), which is indicative of regular, spherical shape.[10]
Another observation from January 2018, by Brigitte Montminy and Katherine McDonald at Minnetonka High School, and Russell Durkee at the Shed of Science Observatory (H39) in Minnetonka, Minnesota, determined a concurring period of26.63±0.03 hours with an amplitude of0.12±0.02 magnitude (U=2+).[11] Federico Manzini at the Sozzago Astronomical Station (A12) obtained the object's first lightcurve in December 2006, measuring a period of17.772±0.007 hours and an amplitude0.06±0.01 magnitude (U=2).[9][12]
According to the surveys carried out by the Infrared Astronomical SatelliteIRAS, theNEOWISE mission of NASA'sWide-field Infrared Survey Explorer (WISE), and the JapaneseAkari satellite,Angelica measures53.63±1.3,60.857±0.198 and64.11±0.74 kilometers in diameter, and its surface has analbedo of0.0739±0.004,0.058±0.007 and0.052±0.002, respectively.[6][7][8] Earlier published measurements by the WISE team gives largermean diameter of71.59±0.55 km and76.741±0.994 km.[9] TheCollaborative Asteroid Lightcurve Link derives an albedo of 0.0515 and a diameter of 53.39 km based on anabsolute magnitude of 10.2.[9]
