_Normannia.png) Shape model ofNormannia from itslightcurve | |
| Discovery[1] | |
|---|---|
| Discovered by | K. Reinmuth |
| Discovery site | Heidelberg Obs. |
| Discovery date | 8 August 1932 |
| Designations | |
| (1256) Normannia | |
| Pronunciation | /nɔːrˈmæniə/[2] |
Named after | Normans/Normandy[3] (people/region in France) |
| 1932 PD · 1930 KO | |
| main-belt · (outer)[1] Hilda[4][5][6] · background[7] | |
| Orbital characteristics[1] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 87.43 yr (31,933 days) |
| Aphelion | 4.1995AU |
| Perihelion | 3.5903 AU |
| 3.8949 AU | |
| Eccentricity | 0.0782 |
| 7.69yr (2,808 days) | |
| 5.5363° | |
| 0° 7m 41.52s / day | |
| Inclination | 4.1732° |
| 236.94° | |
| 101.06° | |
| Physical characteristics | |
| Dimensions | 68.253±0.436 km[8] 69.02 km(derived)[5] 69.22±2.8 km[9] 73.26±2.34 km[10] |
| 6.4±0.1h(poor)[a] 6.8 h(poor)[11] 18.13±0.02 h[6] 18.8(poor) h[12] 488.063±7.4017 h[13] | |
| 0.0364(derived)[5] 0.046±0.003[10] 0.05±0.01[8] 0.0504±0.004[9] 0.052±0.010[8] | |
| Tholen =D[1][5] · D[8][14] B–V = 0.737[1] U–B = 0.239[1] | |
| 9.475±0.002(R)[13] · 9.66[1][9][10] · 9.74[11] · 9.94±0.71[5][14] · 10.02[12] | |
1256 Normannia (prov. designation:1932 PD) is a darkHilda asteroid andslow rotator from the outermost regions of theasteroid belt, approximately 69 kilometers (40 miles) in diameter. It was discovered on 8 August 1932, by astronomerKarl Reinmuth at theHeidelberg-Königstuhl State Observatory in Germany.[4] The asteroid was likely named after theNormans who gave their name to the region ofNormandy in France.[3]
Normannia is a member of theHilda group of asteroids, which are in 3:2orbital resonance with the gas-giant Jupiter.[5][6] When applying theHierarchical Clustering Method to itsproper orbital elements,Normannia is abackground asteroid that does not belong to neither theHilda family (001) nor theSchubart family (002),[7] the only twoasteroid families known within the Hilda group.[15]: 23
It orbits the Sun in theoutermost asteroid belt at a distance of 3.6–4.2 AU once every 7 years and 8 months (2,808 days;semi-major axis of 3.89 AU). Its orbit has aneccentricity of 0.08 and aninclination of 4° with respect to theecliptic.[1] The body'sobservation arc begins with its first identification as1930 KO atLowell Observatory in May 1930, more than two years prior to its official discovery observation at Heidelberg.[4]
Thisminor planet was probably named after theNormans ("Norseman"), mainly Danish and Norwegian Vikings who settled in the historical region ofNormandy in northwestern France. The official naming citation was mentioned inThe Names of the Minor Planets byPaul Herget in 1955 (H 115).[3]
In theTholen classification,Normannia is a darkD-type asteroid.[1][5] Observations byPan-STARRS and by theWide-field Infrared Survey Explorer (WISE) also characterized the asteroid as a D-type.[8][14]
In September 2010, a rotationallightcurve ofNormannia was obtained from photometric observations by astronomers at thePalomar Transient Factory in California. Lightcurve analysis gave arotation period of 488.063 hours with a brightness amplitude of 0.39magnitude (U=2).[13] This makes it one of theTop-100 slow rotators known to exist. Other observations gave several poor lightcurves with a much shorter period between 6.4 and 18.8 hours (U=1/1/1/n.a.).[6][11][12][a]
According to the surveys carried out by the Infrared Astronomical SatelliteIRAS, the JapaneseAkari satellite and theNEOWISE mission of NASA's WISE telescope,Normannia measures between 68.253 and 73.26 kilometers in diameter and its surface has analbedo between 0.046 and 0.052.[8][9][10]
TheCollaborative Asteroid Lightcurve Link derives an albedo of 0.0364 and a diameter of 69.02 kilometers based on anabsolute magnitude of 10.02.[5]
