| Discovery[1] | |
|---|---|
| Discovered by | Indiana University (Indiana Asteroid Program) |
| Discovery site | Goethe Link Obs. |
| Discovery date | 7 September 1962 |
| Designations | |
| (1766) Slipher | |
Named after | Vesto Slipherand Earl C. Slipher[2] |
| 1962 RF · 1953 UR 1980 RH5 | |
| main-belt · (middle) Padua[3] | |
| Orbital characteristics[1] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 63.04 yr (23,027 days) |
| Aphelion | 2.9919AU |
| Perihelion | 2.5066 AU |
| 2.7493 AU | |
| Eccentricity | 0.0883 |
| 4.56yr (1,665 days) | |
| 23.827° | |
| 0° 12m 58.32s / day | |
| Inclination | 5.2283° |
| 188.66° | |
| 171.68° | |
| Physical characteristics | |
| Dimensions | 14.37±3.73 km[4] 14.74±5.05 km[5] 18.959±0.211 km[6] 19.099±0.218 km[7] 20.21 km(calculated)[8] 20.29±1.06 km[9] |
| 7.677±0.0145h(S)[8][10] 7.693±0.0145 h(R)[10] | |
| 0.044±0.003[6] 0.057(assumed)[8] 0.0583±0.0096[7] 0.09±0.10[5] 0.091±0.010[9] 0.11±0.13[4] | |
| SMASS =C[1] · X[11] · C[8] | |
| 11.70[9] · 12.150±0.001(R)[10] · 12.20[1][4][8] · 12.3[7] · 12.46[5] · 12.75±0.14[11] | |
1766 Slipher, provisional designation1962 RF, is a Paduanasteroid from the central regions of theasteroid belt, approximately 18 kilometers in diameter. It was discovered on 7 September 1962, by astronomers of theIndiana Asteroid Program atGoethe Link Observatory in Indiana, United States.[12] The asteroid was named after American astronomersVesto Slipher and his brotherEarl C. Slipher.[2]
Slipher is member of the mid-sizedPadua family (507), anasteroid family named after363 Padua and at least 25 million years old. It consists of mostlyX-type asteroids, that were previously associated to110 Lydia (the Padua family is therefore also known as Lydia family).[3][13][14]: 23
Slipher orbits the Sun in thecentral main-belt at a distance of 2.5–3.0 AU once every 4 years and 7 months (1,665 days). Its orbit has aneccentricity of 0.09 and aninclination of 5° with respect to theecliptic.[1]
The body'sobservation arc begins with its first identification as1953 UR at the discovering Goethe Link observatory in October 1953, or 9 years prior to its official discovery observation.[12]
In theSMASS classification,Slipher is a carbonaceousC-type asteroid.[1]PanSTARRS photometric survey characterized the asteroid as anX-type asteroid, which is in line with the overallspectral type of the Padua family.[11][14]: 23
In 2012, two rotationallightcurves ofSlipher were obtained from photometric observations by astronomers at thePalomar Transient Factory in California. Lightcurve analysis gave arotation period of 7.677 and 7.693 hours with a brightness variation of 0.20 and 0.19magnitude in the S- and R-band, respectively (U=2/2).[10]
According to the surveys carried out by the JapaneseAkari satellite and theNEOWISE mission of NASA'sWide-field Infrared Survey Explorer,Slipher measures between 14.37 and 20.29 kilometers in diameter and its surface has analbedo between 0.044 and 0.11.[4][5][6][7][9]
TheCollaborative Asteroid Lightcurve Link assumes a standard albedo for carbonaceous asteroids of 0.057 and calculates a diameter of 20.21 kilometers based on anabsolute magnitude of 12.2.[8]
Thisminor planet was named after the brothersVesto Slipher (1876–1969) andEarl C. Slipher (1883–1964), both graduates ofIndiana University. Vesto Slipher was a pioneer investigator of the spectra of the planets, and was the first to measure the redshifts of galaxies, which was instrumental for Hubble's discovery of theexpanding Universe. Earl Slipher developed and improved the direct photography of the planets. His photographs are the only continuous and systematic record of the appearance of the planets for a period of more than half a century.[2]
Thelunar andMartian Slipher craters were also named after the two brothers.[2] The officialnaming citation was published by theMinor Planet Center on 20 February 1971 (M.P.C. 3144).[15]
