1747 Wright

1747 Wright, provisional designation 1947 NH, is a stony asteroid and a sizable Mars-crosser, approximately 6 kilometers in diameter.

1747 Wright
1747Wright (Lightcurve Inversion).png
Lightcurve-based 3D-model of Wright
Discovery [1]
Discovered byC. A. Wirtanen
Discovery siteLick Obs.
Discovery date14 July 1947
(1747) Wright
Named after
William Wright
(observatory's director)[2]
1947 NH
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 0
Observation arc69.24 yr (25,290 days)
Aphelion1.8977 AU
Perihelion1.5207 AU
1.7092 AU
2.23 yr (816 days)
0° 26m 27.96s / day
Physical characteristics
Dimensions5.17±0.24 km [5]
6.35±0.6 km (IRAS:2)[6]
5.28796±0.00005 h[7]
5.2896±0.0002 h[8][9]
5.290±0.001 h[10]
0.2005±0.043 (IRAS:2)[6]
Tholen = unusual, noisy spectrum with resemblances to A-type spectrum [1]
SMASS = Sl [1]
Bus–DeMeo = Sw [11]

It was discovered on 14 July 1947, by American astronomer Carl Wirtanen at Lick Observatory on Mount Hamilton near San Jose, California.[3] It was named in memory of astronomer William Hammond Wright.[2]

Orbit and classificationEdit

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 an eccentricity of 0.11 and an inclination of 21° with respect to the ecliptic.[1] As no precoveries were taken and no previous identifications were made, Wright's observation arc begins with its official discovery observation at Mount Hamilton in 1947.[3]

Physical characteristicsEdit

Spectral type and mineralogyEdit

In the SMASS taxonomic system, Wright is an Sl-type, which transitions between the common stony S-type and the less common L-type asteroids.[1] In the Tholen classification, this asteroid could not be assigned to a specific type. Its spectrum was unusual and noisy and resembled that of an A-type asteroid.

In 2012, Wright was observed in the near-infrared using the SpeX instrument of the NASA Infrared Telescope Facility on Mauna Kea, Hawaii. The spectral measurement indicate that Wright is not an olivine-rich A-type, but rather similar to the ordinary chondrites, with the common H chondrite as the most likely meteorite analogue for the asteroid's composition, as the spectra strongly indicate the presence of rock-forming pyroxenes minerals. The team of astronomers also characterized Wright as an Sw class asteroid using the Bus–DeMeo taxonomic system.[11]

Diameter and albedoEdit

According to the surveys carried out by the Infrared Astronomical Satellite IRAS and the Japanese Akari satellite, the asteroid measures 5.17 and 6.35 kilometers in diameter and its surface has an albedo of 0.20 and 0.32, respectively.[5][6] The Collaborative Asteroid Lightcurve Link agrees with the results obtained by IRAS.[4]


In July 2005, a rotational lightcurve of Wright was obtained by astronomers Reiner Stoss, Jaime Nomen, Salvador Sánchez and Raoul Behrend at the Mallorca Observatory, Spain. Lightcurve analysis gave a well-defined rotation period of 5.2896 hours with a brightness variation of 0.61 magnitude (U=3).[8][9]

In July 2014, another, concurring lightcurve with a period of 5.28796 hours and an amplitude of 0.53 was obtained by Robert Stephens at the Trojan Station of the Center for Solar System Studies (U81) in Landers, southern California.[10]


This minor planet was named in memory of American astronomer William Hammond Wright (1871–1959), staff member and later director of the discovering Lick Observatory until 1942. A pioneer in astrophysics, his large, wide-field 20-inch Carnegie double astrograph 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 official naming citation was published by the Minor Planet Center on 20 February 1976 (M.P.C. 3934).[13] Wright is also honored by the Martian and lunar craters Wright.[2]


  1. ^ a b c d e f g h "JPL Small-Body Database Browser: 1747 Wright (1947 NH)" (2016-10-09 last obs.). Jet Propulsion Laboratory. Retrieved 7 June 2017. CS1 maint: discouraged parameter (link)
  2. ^ a b c d Schmadel, Lutz D. (2007). "(1747) Wright". Dictionary of Minor Planet Names – (1747) Wright. Springer Berlin Heidelberg. p. 139. doi:10.1007/978-3-540-29925-7_1748. ISBN 978-3-540-00238-3.
  3. ^ a b c "1747 Wright (1947 NH)". Minor Planet Center. Retrieved 29 October 2016. CS1 maint: discouraged parameter (link)
  4. ^ a b c "LCDB Data for (1747) Wright". Asteroid Lightcurve Database (LCDB). Retrieved 29 October 2016. CS1 maint: discouraged parameter (link)
  5. ^ a b c d Usui, Fumihiko; Kuroda, Daisuke; Müller, Thomas G.; Hasegawa, Sunao; Ishiguro, Masateru; Ootsubo, Takafumi; et al. (October 2011). "Asteroid Catalog Using Akari: AKARI/IRC Mid-Infrared Asteroid Survey". Publications of the Astronomical Society of Japan. 63 (5): 1117–1138. Bibcode:2011PASJ...63.1117U. doi:10.1093/pasj/63.5.1117. Retrieved 17 October 2019. (online, AcuA catalog p. 153)
  6. ^ a b c d Tedesco, E. F.; Noah, P. V.; Noah, M.; Price, S. D. (October 2004). "IRAS Minor Planet Survey V6.0". NASA Planetary Data System – IRAS-A-FPA-3-RDR-IMPS-V6.0. Bibcode:2004PDSS...12.....T. Retrieved 17 October 2019. CS1 maint: discouraged parameter (link)
  7. ^ Hanus, J.; Durech, J.; Broz, M.; Warner, B. D.; Pilcher, F.; Stephens, R.; et al. (June 2011). "A study of asteroid pole-latitude distribution based on an extended set of shape models derived by the lightcurve inversion method". Astronomy & Astrophysics. 530: 16. arXiv:1104.4114. Bibcode:2011A&A...530A.134H. doi:10.1051/0004-6361/201116738. Retrieved 18 November 2015.
  8. ^ a b Stoss, Reiner; Nomen, Jaime; Sanchez, Salvador; Behrend, Raoul (June 2006). "Lightcurve of minor planet 1747 Wright". The Minor Planet Bulletin. 33 (2): 33. Bibcode:2006MPBu...33...33S. ISSN 1052-8091. Retrieved 18 November 2015.
  9. ^ a b Behrend, Raoul. "Asteroids and comets rotation curves – (1747) Wright". Geneva Observatory. Retrieved 29 October 2016. CS1 maint: discouraged parameter (link)
  10. ^ a b Stephens, Robert D. (January 2015). "Asteroids Observed from CS3: 2014 July - September". The Minor Planet Bulletin. 42 (1): 70–74. Bibcode:2015MPBu...42...70S. ISSN 1052-8091. Retrieved 18 November 2015.
  11. ^ a b Michael P. Lucas; Joshua P. Emery. "Surface Mineralogy of Mars-Crossing Asteroid 1747 Wright" (PDF). Retrieved 25 August 2017. CS1 maint: discouraged parameter (link)
  12. ^ "Carnegie Double Astrograph". Lick Observatory. Retrieved 29 October 2016. CS1 maint: discouraged parameter (link)
  13. ^ Schmadel, Lutz D. (2009). "Appendix – Publication Dates of the MPCs". Dictionary of Minor Planet Names – Addendum to Fifth Edition (2006–2008). Springer Berlin Heidelberg. p. 221. doi:10.1007/978-3-642-01965-4. ISBN 978-3-642-01964-7.

External linksEdit