| Discovery[1] | |
|---|---|
| Discovered by | K. Reinmuth |
| Discovery site | Heidelberg Obs. |
| Discovery date | 29 September 1929 |
| Designations | |
| (1161) Thessalia | |
| Pronunciation | /θɪˈseɪliə/[2] |
Named after | Thessaly(Greek region)[3] |
| 1929 SF · 1931 BB | |
| main-belt · (outer) background[4] | |
| Orbital characteristics[1] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 87.76 yr (32,056 days) |
| Aphelion | 3.4488AU |
| Perihelion | 2.8975 AU |
| 3.1732 AU | |
| Eccentricity | 0.0869 |
| 5.65yr (2,065 days) | |
| 213.02° | |
| 0° 10m 27.84s / day | |
| Inclination | 9.3913° |
| 72.567° | |
| 309.20° | |
| Physical characteristics | |
| Dimensions | 21.498±0.184 km[5] |
| 0.065±0.010[6] | |
| 11.2[1] | |
1161 Thessalia, provisional designation1929 SF, is a dark backgroundasteroid from the outer regions of theasteroid belt, approximately 21 kilometers in diameter. It was discovered on 29 September 1929, by German astronomerKarl Reinmuth at theHeidelberg-Königstuhl State Observatory.[7] It was named for the Greek regionThessaly.[3]
Thessalia is a non-family asteroid from the main belt'sbackground population.[4] It orbits the Sun in theouter main-belt at a distance of 2.9–3.4 AU once every 5 years and 8 months (2,065 days). Its orbit has aneccentricity of 0.09 and aninclination of 9° with respect to theecliptic.[1] The body'sobservation arc begins at Heidelberg, five weeks after its official discovery observation.[7]
According to the survey carried out by theNEOWISE mission of NASA'sWide-field Infrared Survey Explorer,Thessalia measures 21.498 kilometers in diameter and its surface has analbedo of 0.065.[5][6]
As of 2017, no rotationallightcurve ofThessalia has been obtained from photometric observations. The asteroid'srotation period, poles and shape remain unknown.[8]
Thisminor planet was named for theThessaly region in eastern Greece. The subsequently numbered minor planet1162 Larissa was named after the region's capital. The official naming citation was mentioned inThe Names of the Minor Planets byPaul Herget in 1955 (H 108).[3]
