| Discovery[1] | |
|---|---|
| Discovered by | K. Reinmuth |
| Discovery site | Heidelberg Obs. |
| Discovery date | 5 October 1931 |
| Designations | |
| (1227) Geranium | |
| Pronunciation | /dʒəˈreɪniəm/[2] |
Named after | Geranium[3] (flowering plant) |
| 1931 TD · 1934 CL1 | |
| main-belt · (outer)[1][4] background[5] | |
| Orbital characteristics[1] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 86.14 yr (31,463d) |
| Aphelion | 3.8358AU |
| Perihelion | 2.6018 AU |
| 3.2188 AU | |
| Eccentricity | 0.1917 |
| 5.77yr (2,109 days) | |
| 23.697° | |
| 0° 10m 14.52s / day | |
| Inclination | 16.492° |
| 0.7016° | |
| 302.84° | |
| Physical characteristics | |
| Dimensions | 41.46 km(derived)[4] 46.08±0.80 km[6] 46.269±0.140 km[7] 51.025±0.535 km[8] |
| 12.363±0.004h[9] | |
| 0.0492(derived)[4] 0.0619±0.0119[8] 0.071±0.016[7] 0.076±0.003[6] | |
| C(SDSS–MFB)[4] | |
| 10.10[6][8] · 10.8[1][4] | |
1227 Geranium, provisional designation1931 TD, is a carbonaceous backgroundasteroid from the outer regions of theasteroid belt, approximately 46 kilometers in diameter. It was discovered on 5 October 1931, by German astronomerKarl Reinmuth at theHeidelberg-Königstuhl State Observatory.[10] The asteroid was named for the flowering plantGeranium (cranesbills).[3]
Geranium is a non-family asteroid from the main belt'sbackground population.[5] It orbits the Sun in theouter main-belt at a distance of 2.6–3.8 AU once every 5 years and 9 months (2,109 days;semi-major axis 3.22 AU). Its orbit has aneccentricity of 0.19 and aninclination of 16° with respect to theecliptic.[1]
The body'sobservation arc begins atUccle Observatory, four days after its official discovery observation at Heidelberg.[10]
Geranium has been characterized as a carbonaceousC-type asteroid bySDSS–MFB (Masi Foglia Bus).[4]
In April 2010, a rotationallightcurve ofGeranium was obtained from photometric observations by astronomers at theOakley Southern Sky Observatory in Australia. Lightcurve analysis gave a well-definedrotation period of 12.363 hours with a brightness amplitude of 0.08magnitude, indicative for a rather spherical shape (U=3).[9]
According to the surveys carried out by the JapaneseAkari satellite and theNEOWISE mission of NASA'sWide-field Infrared Survey Explorer,Geranium measures between 46.08 and 51.025 kilometers in diameter and its surface has analbedo between 0.0619 and 0.076.[6][7][8]
TheCollaborative Asteroid Lightcurve Link derives an albedo of 0.0492 and a diameter of 41.46 kilometers based on anabsolute magnitude of 10.8.[4]
Thisminor planet was named afterGeranium, a genus of flowering plants commonly known as "cranesbills". The official naming citation was mentioned inThe Names of the Minor Planets byPaul Herget in 1955 (H 113).[3]
The initials of the minor planets(1227) through(1234), all discovered by Reinmuth, spell out "G. Stracke".Gustav Stracke was a German astronomer and orbit computer, who had asked that no planet be named after him. In this manner Reinmuth was able to honour the man whilst honoring his wish. Nevertheless, Reinmuth directly honored Stracke by naming planet1019 Strackea later on.[11] The astronomerBrian Marsden was honored by the same type of meta-naming using consecutive initial letters in 1995, spelling out "Brian M." in the sequence of minor planets(5694) through(5699).[11]
Due to his many discoveries,Karl Reinmuth submitted a large list of 66 newly named asteroids in the early 1930s. The list covered his discoveries with numbers between(1009) and(1200). This list also contained a sequence of 28 asteroids, starting with1054 Forsytia, that were all named after plants, in particularflowering plants(also see list of minor planets named after animals and plants).[12]