| Discovery[1] | |
|---|---|
| Discovered by | K. Reinmuth |
| Discovery site | Heidelberg Obs. |
| Discovery date | 10 October 1920 |
| Designations | |
| (940) Kordula | |
Named after | Name picked from the almanac Lahrer Hinkender Bote[2] |
| A920 TE · 1947 BG 1947 EB · 1954 DB 1963 PC · 1920 HT | |
| main-belt[1] · (outer)[3] Cybele | |
| Orbital characteristics[3] | |
| Epoch 31 May 2020 (JD 2459000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 99.24yr (36,248 d) |
| Aphelion | 3.9375AU |
| Perihelion | 2.7940 AU |
| 3.3657 AU | |
| Eccentricity | 0.1699 |
| 6.17 yr (2,255 d) | |
| 41.359° | |
| 0° 9m 34.56s / day | |
| Inclination | 6.2428° |
| 66.320° | |
| 283.51° | |
| Physical characteristics | |
| 15.57±0.36 h[7][8] | |
| 9.2[3] 9.3[1] | |
940 Kordula (prov. designation:A920 TEor1920 HT) is a large and darkCybele asteroid from the outermost region of theasteroid belt, approximately 80 kilometers (50 miles) in diameter. It was discovered on 10 October 1920, by astronomerKarl Reinmuth at theHeidelberg-Königstuhl State Observatory in Germany.[1] The carbonaceousF-type asteroid (FC) has arotation period of 15.6 hours. It was named "Kordula", a common German female name unrelated to the discoverer's contemporaries, that was taken from the almanacLahrer Hinkender Bote.[2]
Kordula is a non-family asteroid of the main belt'sbackground population when applying thehierarchical clustering method to itsproper orbital elements.[9] It is located in the orbital region of theCybele asteroids. The Cybeles are the last outpost of the extended asteroid belt, already located beyond theHecuba gap. It orbits the Sun in theoutermost asteroid belt at a distance of 2.8–3.9 AU once every 6 years and 2 months (2,255 days;semi-major axis of 3.37 AU). Its orbit has aneccentricity of 0.17 and aninclination of 6° with respect to theecliptic.[3] The body'sobservation arc begins atHeidelberg Observatory on 11 October 1920, the night after its official discovery observation.[1]
Thisminor planet was named "Kordula", after a female name picked from theLahrer Hinkender Bote, published inLahr, southern Germany. AHinkender Bote (lit. "limping messenger") was a very popularalmanac, especially in thealemannic-speaking region from the late 17th throughout the early 20th century. Thecalendar section containsfeast days, the dates of important fairs andastronomical ephemerides. The calendar contains a Germanname day analogue for the respective catholic and protestant feast-days(entry not found).[10] "Kordula" derives from Cordula and may refer toSaint Cordula.
As with 22 other asteroids – starting with913 Otila, and ending with1144 Oda – Reinmuth selected names from this calendar due to his many asteroid discoveries that he had trouble thinking of proper names. These names are not related to the discoverer's contemporaries.Lutz Schmadel, the author of theDictionary of Minor Planet Names learned about Reinmuth's source of inspiration from private communications with Dutch astronomerIngrid van Houten-Groeneveld, who worked as a young astronomer at Heidelberg.[2]
In theTholen classification,Kordula is closest to anF-type asteroid, and somewhat similar to that to a common carbonaceousC-type asteroid.[3][11]
In October 1999, a rotationallightcurve ofKordula was obtained fromphotometric observations byVincenzo Zappalà and his Italian colleagues. Lightcurve analysis gave a well-definedrotation period of15.57 hours with a brightness amplitude of0.36magnitude (U=3).[7][8]
According to the surveys carried out by theNEOWISE mission of NASA'sWide-field Infrared Survey Explorer (WISE), the Infrared Astronomical SatelliteIRAS, and the JapaneseAkari satellite,Kordula measures (79.852±0.504), (87.21±2.6) and (87.65±1.50) kilometers in diameter, and its surface has analbedo of (0.041±0.009), (0.0352±0.002) and (0.035±0.002), respectively.[4][5][6]
Further published mean-diameters and albedos by the WISE team include (77.941±26.705 km), (87.10±25.52 km), (87.29±33.02 km), and (93.192±1.325 km) with corresponding albedos of (0.044±0.024), (0.04±0.03), (0.04±0.03), and (0.0308±0.0066).[11][7] TheCollaborative Asteroid Lightcurve Link adopts the results from IRAS, that is, an albedo of 0.0352 and a diameter of 87.21 km based on anabsolute magnitude of 9.55.[7][11]
