.png) Lightcurve-based 3D-model ofWright | |
| Discovery[1] | |
|---|---|
| Discovered by | C. A. Wirtanen |
| Discovery site | Lick Obs. |
| Discovery date | 14 July 1947 |
| Designations | |
| (1747) Wright | |
Named after | William Wright (observatory's director)[2] |
| 1947 NH | |
| Mars-crosser[1][3][4] | |
| Orbital characteristics[1] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 69.24 yr (25,290 days) |
| Aphelion | 1.8977AU |
| Perihelion | 1.5207 AU |
| 1.7092 AU | |
| Eccentricity | 0.1103 |
| 2.23yr (816 days) | |
| 174.63° | |
| 0° 26m 27.96s / day | |
| Inclination | 21.416° |
| 268.39° | |
| 340.43° | |
| Physical characteristics | |
| Dimensions | 5.17±0.24 km[5] 6.35±0.6 km(IRAS:2)[6] |
| 5.28796±0.00005h[7] 5.2896±0.0002 h[8][9] 5.290±0.001 h[10] | |
| 0.2005±0.043(IRAS:2)[6] 0.321±0.034[5] | |
| Tholen = unusual, noisy spectrum with resemblances to A-type spectrum[1] SMASS = Sl[1] Bus–DeMeo = Sw[11] | |
| 13.35[1][4][5][6] | |
1747 Wright, provisional designation1947 NH, is a stonyasteroid and a sizableMars-crosser, approximately 6 kilometers in diameter.
It was discovered on 14 July 1947, by American astronomerCarl Wirtanen atLick Observatory on Mount Hamilton near San Jose, California.[3] It was named in memory of astronomerWilliam Hammond Wright.[2]
Wright orbits the Sun at a distance of 1.5–1.9 AU once every 2 years and 3 months (816 days). Its orbit has aneccentricity of 0.11 and aninclination of 21° with respect to theecliptic.[1] As noprecoveries were taken and no previous identifications were made,Wright'sobservation arc begins with its official discovery observation at Mount Hamilton in 1947.[3]
In theSMASS taxonomic system,Wright is an Sl-type, which transitions between the common stonyS-type and the less commonL-type asteroids.[1] In theTholen classification, this asteroid could not be assigned to a specific type. Its spectrum was unusual and noisy and resembled that of anA-type asteroid.
In 2012,Wright was observed in the near-infrared using theSpeX instrument of theNASA Infrared Telescope Facility on Mauna Kea, Hawaii. The spectral measurement indicate thatWright is not an olivine-rich A-type, but rather similar to theordinary chondrites, with the commonH chondrite as the most likelymeteorite analogue for the asteroid's composition, as the spectra strongly indicate the presence of rock-formingpyroxenes minerals. The team of astronomers also characterizedWright as anSw class asteroid using the Bus–DeMeo taxonomic system.[11]
According to the surveys carried out by the Infrared Astronomical SatelliteIRAS and the JapaneseAkari satellite, the asteroid measures 5.17 and 6.35 kilometers in diameter and its surface has analbedo of 0.20 and 0.32, respectively.[5][6] TheCollaborative Asteroid Lightcurve Link agrees with the results obtained by IRAS.[4]
In July 2005, a rotationallightcurve ofWright was obtained by astronomersReiner Stoss,Jaime Nomen,Salvador Sánchez andRaoul Behrend at theMallorca Observatory, Spain. Lightcurve analysis gave a well-definedrotation period of5.2896 hours with a brightness variation of 0.61magnitude (U=3).[8][9]
In July 2014, another, concurring lightcurve with a period of5.28796 hours and an amplitude of 0.53 was obtained byRobert Stephens at the Trojan Station of the Center for Solar System Studies (U81) in Landers, southern California.[10]
Thisminor planet was named in memory of American astronomerWilliam Hammond Wright (1871–1959), staff member and later director of the discovering Lick Observatory until 1942. A pioneer in astrophysics, his large, wide-field20-inch Carnegie doubleastrograph built for the observatory's proper motion survey (first light in 1941), was using distant galaxies ("spiral nebulae") as object references. During this survey, many comets and asteroids were discovered as a by-product.[2][12] The officialnaming citation was published by theMinor Planet Center on 20 February 1976 (M.P.C. 3934).[13] Wright is also honored by theMartian andlunar cratersWright.[2]
