_Einstein.png) Shape model ofEinstein from itslightcurve | |
| Discovery[1] | |
|---|---|
| Discovered by | P. Wild |
| Discovery site | Zimmerwald Obs. |
| Discovery date | 5 March 1973 |
| Designations | |
| (2001) Einstein | |
Named after | Albert Einstein(physicist)[2] |
| 1973 EB | |
| main-belt · Hungaria[3][4] | |
| Orbital characteristics[1] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 43.43 yr (15,864 days) |
| Aphelion | 2.1242AU |
| Perihelion | 1.7430 AU |
| 1.9336 AU | |
| Eccentricity | 0.0986 |
| 2.69yr (982 days) | |
| 150.59° | |
| 0° 21m 59.76s / day | |
| Inclination | 22.683° |
| 357.08° | |
| 217.74° | |
| Physical characteristics | |
| 3.975±0.154 km[5][6] 5.66 km(calculated)[7] | |
| 5.4846±0.0001 h[8] 5.485±0.002 h[9] 5.48503±0.00005 h(S)[10] 5.487±0.001 h[11] | |
| 0.40(assumed)[7] 0.810±0.169[5][6] | |
| X(Tholen), Xe(SMASS)[1] X[7] · E[5] B–V = 0.720[1] U–B = 0.261[1] | |
| 12.85[1][5][7] | |
2001 Einstein (prov. designation:1973 EB) is a brightHungaria asteroid from the innermost region of theasteroid belt. It was discovered by Swiss astronomerPaul Wild atZimmerwald Observatory near Bern, Switzerland, on 5 March 1973.[3] TheX-type asteroid (Xe) has arotation period of 5.5 hours and measures approximately 5 kilometers (3.1 miles) in diameter. It is named after physicistAlbert Einstein (1879–1955).[2]
Einstein is a member of theHungaria family, which form the innermost dense concentration of asteroids in the Solar System. It orbits the Sun in theinner main-belt at a distance of 1.7–2.1 AU once every 2 years and 8 months (982 days). Its orbit has aneccentricity of 0.10 and aninclination of 23° with respect to theecliptic.[1] As noprecoveries were taken, the asteroid'sobservation arc begins with its discovery in 1973.[3]
Thisminor planet was named in honour of the German-born, Swiss–American physicist and NobelistAlbert Einstein (1879–1955). It is considered suitable, that the body discovered at Bern is named after the 1921Nobel Prize in Physics laureate, since it was the place where he had his golden years while working as a clerk at the Swiss Patent Office in Bern. He is also honored by the lunar craterEinstein.[2] The officialnaming citation was published by theMinor Planet Center on 15 October 1977 (M.P.C. 4237).[12]Arthur C. Clarke joked in the postscript of his novel3001: The Final Odyssey that he was hoping asteroid 2001 would be named after him, but it was named for Einstein first. Asteroid 3001 was named3001 Michelangelo. Clarke was later honoured with asteroid4923 Clarke, named together with5020 Asimov.
TheTholen classification,Einstein is anX-type asteroid, while in theSMASS classification, it is an Xe-subtype which transitions from the X-type to the very brightE-type asteroid.
Several rotationallightcurves for this asteroid were obtained fromphotometric observations. In December 2004, the first lightcurve by American astronomerBrian Warner at his Palmer Divide Observatory (PDS) in Colorado, gave arotation period of5.487 hours with a brightness variation of0.66 inmagnitude (U=3).[11] Between 2008 and 2012, three additional lightcurves at the PDS gave an almost identical period of 5.485 hours with an amplitude of 0.67, 0.74 and 1.02, respectively (U=3/3/3).[9][13][14] Other lightcurves were obtained by Hanuš at the FrenchCNES and other institutions, which gave a period of5.48503 hours (U=n.a.),[10] and by Italian astronomer Federico Manzini at SAS observatory in Novara, Jean Strajnic and Raoul Behrend from December 2012, which rendered a period of5.4846 hours with an amplitude of 0.66 in magnitude (U=2+).[8]
According to the survey carried out by theNEOWISE mission of NASA's space-basedWide-field Infrared Survey Explorer (WISE), the asteroid measures 4.0 km in diameter and its surface has an exceptionally highalbedo of 0.81, for which WISE assigns anE-type.[5] TheCollaborative Asteroid Lightcurve Link assumes a lower, yet still high albedo of 0.40 and hence calculates a larger diameter of 5.7 kilometers, as the lower the albedo, the larger the body's diameter for a constant absolute magnitude.[7]
