_Vassar.png) Modelled shape ofVassar from itslightcurve | |
| Discovery[1] | |
|---|---|
| Discovered by | G. van Biesbroeck |
| Discovery site | Yerkes Obs. |
| Discovery date | 27 July 1933 |
| Designations | |
| (1312) Vassar | |
Named after | Vassar College (Vassar Observatory)[2] |
| 1933 OT · 1944 QE A908 CD | |
| main-belt · (outer)[3] Alauda[4] | |
| Orbital characteristics[1] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 83.67 yr (30,562 days) |
| Aphelion | 3.7605AU |
| Perihelion | 2.4268 AU |
| 3.0937 AU | |
| Eccentricity | 0.2156 |
| 5.44yr (1,988 days) | |
| 104.98° | |
| 0° 10m 51.96s / day | |
| Inclination | 21.901° |
| 129.45° | |
| 261.33° | |
| Physical characteristics | |
| Dimensions | 27.56±6.84 km[5] 32.70±1.29 km[6] 36.28±1.1 km(IRAS:6)[7] 36.32 km(derived)[3] |
| 7.93189±0.00001 h[8] 7.93190±0.00005 h[9] 7.932±0.002h[a] | |
| 0.0643±0.004(IRAS:6)[7] 0.0703(derived)[3] 0.081±0.007[6] 0.09±0.07[5] | |
| C[3] | |
| 10.68[5] · 10.7[1][3] · 10.76±0.44[10] · 10.80[6] | |
1312 Vassar, provisional designation1933 OT, is a carbonaceous Alaudaasteroid from the outer region of theasteroid belt, approximately 30 kilometers in diameter. It was discovered on 27 July 1933, by Belgian–American astronomerGeorge Van Biesbroeck atYerkes Observatory in Wisconsin, United States.[11] The asteroid was named for the AmericanVassar College.
Vassar is a member of theAlauda family (902),[4] a largefamily of typically bright carbonaceous asteroids and named after its parent body,702 Alauda.[12]: 23
It orbits the Sun in theouter main-belt at a distance of 2.4–3.8 AU once every 5 years and 5 months (1,988 days). Its orbit has aneccentricity of 0.22 and aninclination of 22° with respect to theecliptic.[1] In 1908, it was first identified asA908 CD atHeidelberg Observatory. The body'sobservation arc begins with its official discovery observation at Yerkes in 1933.[11]
In November 2011 American amateur astronomerDavid Higgins obtained a rotationallightcurve ofVassar from photometric observations taken at the Hunters Hill Observatory (E14) in Australia. It gave a well-definedrotation period of 7.932 hours with a brightness variation of 0.35magnitude (U=3).[a] In 2016, two modeled lightcurves were derived using data from the Lowell photometric database and other sources, giving a concurring period of 7.93189 and 7.93190 hours and a spin axis of (104.0°, −50°) and (251.0°, −23.0°) inecliptic coordinates, respectively (U=n.a.).[8][9]
According to the surveys carried out by the Infrared Astronomical SatelliteIRAS, the JapaneseAkari satellite, and NASA'sWide-field Infrared Survey Explorer with its subsequentNEOWISE mission,Vassar measures between 27.56 and 36.28 kilometers in diameter, and its surface has analbedo between 0.064 and 0.09.[5][6][7] TheCollaborative Asteroid Lightcurve Link agrees with the results obtained by IRAS and derives an albedo of 0.0703 and a diameter of 36.32 kilometers with anabsolute magnitude of 10.7.[3]
Thisminor planet was named by American astronomerMaud Worcester Makemson (1891–1977) after the U.SVassar College (formerly: Vassar Female College), located in New York state. Makemson, who computed the asteroid's orbit, was a teacher at the private elite school and director of itsVassar College Observatory.[2] Naming citation was first published inThe Names of the Minor Planets byPaul Herget in 1955 (H 120).[2]
