| Discovery[1] | |
|---|---|
| Discovered by | K. Reinmuth |
| Discovery site | Heidelberg Obs. |
| Discovery date | 31 January 1924 |
| Designations | |
| (1015) Christa | |
Named after | unknown[2] |
| 1924 QF · A916 UE | |
| main-belt · (outer)[3][4] background[5] | |
| Orbital characteristics[3] | |
| Epoch 23 March 2018 (JD 2458200.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 93.42yr (34,123 d) |
| Aphelion | 3.4848AU |
| Perihelion | 2.9262 AU |
| 3.2055 AU | |
| Eccentricity | 0.0871 |
| 5.74 yr (2,096 d) | |
| 232.16° | |
| 0° 10m 18.12s / day | |
| Inclination | 9.4449° |
| 120.15° | |
| 286.50° | |
| Physical characteristics | |
| 82.350±1.096 km[6] 95.51±27.79 km[7] 96.592±2.896 km[8] 96.94±3.6 km[9] 99.88±36.30 km[10] 101.04±1.37 km[11] | |
| Mass | (4.77±0.68)×1010 kg[12] |
Meandensity | 9.17±1.46 g/cm3[12] |
| 11.230±0.004 h[13][a] 12.189±0.001 h[14] | |
| 0.04±0.04[7][10] 0.042±0.001[11] 0.0459±0.004[9] 0.0463±0.0062[8] 0.048±0.009[15] 0.064±0.016[6] | |
| Tholen =C[3][4] SMASS =Xc[3][12] · P[8] B–V = 0.693[3] U–B = 0.320[3] | |
| 9.03[3][4][6][9][8][10][11] 9.13[7] · 9.46±0.45[16] | |
1015 Christa, provisional designation1924 QF, is a dark backgroundasteroid from the outermost regions of theasteroid belt, approximately 96 kilometers (60 miles) in diameter. It was discovered on 31 January 1924, by German astronomerKarl Reinmuth at theHeidelberg-Königstuhl State Observatory in southwest Germany.[1] Themeaning of this asteroids's name is unknown.[2]
Christa is a non-family asteroid from the main belt'sbackground population.[5] It orbits the Sun in theoutermost asteroid belt at a distance of 2.9–3.5 AU once every 5 years and 9 months (2,096 days;semi-major axis of 3.21 AU). Its orbit has aneccentricity of 0.09 and aninclination of 9° with respect to theecliptic.[3]
The asteroid was first observed asA916 UE at theSimeiz Observatory in October 1916. The body'sobservation arc begins at Heidelberg in February 1924, two days after its official discovery observation.[1]
In theTholen classification,Christa is a commonC-type asteroid,[3][4] while in theSMASS classification, it is a Xc-subtype that transitions from the carbonaceous C-type to theX-type asteroids.[3][12] It has also been characterized as a primitiveP-type asteroid by theWide-field Infrared Survey Explorer (WISE).[8]
In April 2005, a first rotationallightcurve ofChrista was obtained fromphotometric observations by French amateur astronomers Raymond Poncy andRené Roy. Lightcurve analysis gave arotation period of 12.189 hours with a brightness variation of 0.20magnitude (U=2).[14] In January 2009, a refined period of 11.230 hours and an amplitude of 0.12 magnitude was measured by photometristBrian Warner at hisPalmer Divide Observatory in Colorado, United States (U=3-).[13][a]
According to the surveys carried out by the Infrared Astronomical SatelliteIRAS, the JapaneseAkari satellite and theNEOWISE mission of NASA's WISE telescope,Christa measures between 82.35 and 101.04 kilometers in diameter and its surface has a lowalbedo between 0.04 and 0.064.[6][7][8][9][10][11][15] TheCollaborative Asteroid Lightcurve Link adopts the results obtained by IRAS, that is, an albedo of 0.0459 with a diameter of 96.94 kilometers based on anabsolute magnitude of 9.03.[4]
1015 Christa has been observed tooccult 8 stars between 2005 and 2023.
Any reference of thisminor planet's name to a person or occurrence is unknown.[2]
Among the many thousands ofnamed minor planets,Christa is one of 120 asteroids, for which no official naming citation has been published. All of these low-numbered asteroids have numbers between164 Eva and1514 Ricouxa and were discovered between 1876 and the 1930s, predominantly by astronomersAuguste Charlois,Johann Palisa,Max Wolf andKarl Reinmuth.[17]
