.png) Lightcurve-based 3D-model ofStephania | |
| Discovery[1] | |
|---|---|
| Discovered by | J. Palisa |
| Discovery site | Vienna Obs. |
| Discovery date | 19 May 1881 |
| Designations | |
| (220) Stephania | |
| Pronunciation | /stɪˈfeɪniə/[2] |
Named after | Princess Stéphanie[3] (Belgian royalty) |
| A881 KA · 1925 VE 1931 FP · 1932 UA 1943 WB · 1946 MA 1950 TT4 · 1961 WB | |
| main-belt · (inner)[4] background[5] | |
| Orbital characteristics[1] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 86.28 yr (31,514 days) |
| Aphelion | 2.9543AU |
| Perihelion | 1.7443 AU |
| 2.3493 AU | |
| Eccentricity | 0.2575 |
| 3.60yr (1,315 days) | |
| 239.16° | |
| 0° 16m 25.32s / day | |
| Inclination | 7.5895° |
| 257.92° | |
| 78.480° | |
| Physical characteristics | |
| Dimensions | 31.04 km(derived)[4] 31.12±1.5 km[6] 31.738±0.219 km[7] 31.96±9.77 km[8] 32.29±0.33 km[9] 33±2 km[10] 35.097±0.260 km[11] 38.46±5.77 km[12] |
| 18.19 h[a] 18.198h[13] 18.2±0.2 h[10] 18.21 h[b] | |
| 0.03±0.01[12] 0.05±0.03[8] 0.0571±0.0068[11] 0.0607(derived)[4] 0.069±0.002[9] 0.069±0.016[7] 0.0726±0.007[6] 0.075±0.015[10] | |
| Tholen =XC[1][4] C[14] · P[11] | |
| 11.00[6][9][11] · 11.10[8] · 11.2[1][4] · 11.35[12] | |
220 Stephania is a dark backgroundasteroid from the inner regions of theasteroid belt, approximately 32 km (20 mi) in diameter. It was discovered on 19 May 1881, by Austrian astronomerJohann Palisa at theVienna Observatory.[15] TheC-type asteroid has arotation period of 18.2 hours.[4] It was named afterPrincess Stéphanie of Belgium.[3]
Stephania is a non-family asteroid of the main belt'sbackground population, when applying theHierarchical Clustering Method to itsproper orbital elements.[5] It orbits the Sun in theinner asteroid belt at a distance of 1.7–3.0 AU once every 3 years and 7 months (1,315 days). Its orbit has aneccentricity of 0.26 and aninclination of 8° with respect to theecliptic.[1]
Stephania was discovered byJohann Palisa on May 19, 1881, inVienna.[15] It was the first discovery he made after transferring to the observatory from Pola.[3]
The name honoursCrown Princess Stéphanie (1864–1945), wife of theheir-apparentCrown Prince Rudolf of Austria. The couple was married the year the asteroid was discovered. It was the first time that a naming commemorated a wedding and was given as a wedding gift.[3] The official naming citation was mentioned inThe Names of the Minor Planets byPaul Herget in 1955 (H 27).[3]
In theTholen classification, this asteroid's spectrum is ambiguous, close to anX-type and somewhat similar to that of a carbonaceousC-type asteroid (CX).[4] A French spectroscopic survey that observed two dozens of these X-types classified by Tholen, determined thatStephania is in fact a carbonaceousC-type asteroid (rather than an X-type).[14] TheWide-field Infrared Survey Explorer (WISE) has also characterized it as a primitiveP-type asteroid.[4][11]
Lightcurve data has also been recorded by observers at the Antelope Hill Observatory (H09), which has been designated as an official observatory by theMinor Planet Center.[b]
According to the surveys carried out by the Infrared Astronomical SatelliteIRAS, the JapaneseAkari satellite and theNEOWISE mission of NASA's WISE telescope,Stephania measures between 31.12 and 38.46 kilometers in diameter and its surface has a lowalbedo between 0.03 and 0.075.[6][7][8][9][10][11][12] TheCollaborative Asteroid Lightcurve Link derives an albedo of 0.0607 and a diameter of 31.04 kilometers based on anabsolute magnitude of 11.2.[4]
