751 Faïna (prov. designation: A913 HE or 1913 RK) is a very large background asteroid from the central regions of the asteroid belt, approximately 110 kilometers (68 miles) in diameter. It was discovered on 28 April 1913, by Russian astronomer Grigory Neujmin at the Simeiz Observatory on the Crimean peninsula.[1] The elongated C-type asteroid (Ch) has a rotation period of 23.7 hours. It was named after Faina Mikhajlovna Neujmina, colleague and first wife of the discoverer.[2]

751 Faïna
Discovery [1]
Discovered byG. Neujmin
Discovery siteSimeiz Obs.
Discovery date28 April 1913
Designations
(751) Faïna
Named after
Faina Neujmina [2]
(Wife of the discoverer)
A913 HE · 1913 RK
main-belt[1][3] · (middle)
Faïna[4] · background[5][6]
Orbital characteristics[3]
Epoch 31 May 2020 (JD 2459000.5)
Uncertainty parameter 0
Observation arc106.97 yr (39,072 d)
Aphelion2.9387 AU
Perihelion2.1657 AU
2.5522 AU
Eccentricity0.1514
4.08 yr (1,489 d)
293.41°
0° 14m 30.12s / day
Inclination15.600°
78.849°
302.26°
Physical characteristics
Dimensions132.0 km × 88.2 km[6]
Mean diameter
Mass(3.27±0.58)×1018 kg[11]
Mean density
5.05±0.92 g/cm3[11]
23.678 h[12]
  • 0.047±0.013[9]
  • 0.0497±0.004[8]
  • 0.055±0.002[7]

Orbit and classification edit

Located close to the region of the stony Eunomia family (502),[13] Faïna is a non-family asteroid of the main belt's background population when applying the modern synthetic hierarchical clustering method (HCM) by Nesvorný as well as Milani and Knežević (AstDys).[5][6] However, in the 1995 HCM-analysis by Zappalà,[4] Faïna is the parent body of the tiny Faïna family,[4] which is not recognized by modern analysis. The HCM-method is based on an object's proper orbital elements to group asteroids into families.

Faïna orbits the Sun in the central asteroid belt at a distance of 2.2–2.9 AU once every 4 years and 1 month (1,489 days; semi-major axis of 2.55 AU). Its orbit has an eccentricity of 0.15 and an inclination of 16° with respect to the ecliptic.[3] The body's observation arc begins at Vienna Observatory on 8 May 2013, or two weeks after its official discovery observation by Grigory Neujmin at Simeiz.[1]

Naming edit

This minor planet was named after Faina Mikhajlovna Neujmina, the first wife of the discoverer. Astronomer Lutz Schmadel compiled this naming citation, based on his private communication with "N. S. Samojlova-Yakhontova", as neither the Minor Planet Circulars nor The Names of the Minor Planets give any information about this asteroid's name.[2][14]

Physical characteristics edit

In the Tholen classification, Faïna is a common, carbonaceous C-type asteroid, while in the Bus–Binzel SMASS classification, it is a hydrated carbonaceous Ch-type.[3][6]

Rotation period edit

In late 1988, a rotational lightcurve of Faïna was obtained from photometric observations by Richard Miles at the Manley Observatory near Chester in northwest England. Lightcurve analysis gave a well-defined rotation period of 23.678 hours with a brightness variation of 0.36 magnitude (U=3).[12] Alternative observations by Roberto Crippa, Federico Manzini (2006) as well as by Bruno Christmann (2019) determined a period of 10+ and (11.846±0.007) hours (or half the period) with an amplitude of 0.02 and 0.18±0.01 magnitude (U=1/2).[13][15]

Diameter and albedo edit

According to the surveys carried out by the Japanese Akari satellite, the Infrared Astronomical Satellite IRAS, and the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer (WISE), Faïna measures (106.81±1.28), (110.50±4.3) and (113.699±2.449) kilometers in diameter and its surface has a low albedo of (0.055±0.002), (0.0497±0.004) and (0.047±0.013), respectively.[7][8][9][10]

The Collaborative Asteroid Lightcurve Link adopts the results from IRAS, that is, an albedo of 0.0497 and a diameter of 110.50 kilometers based on an absolute magnitude of 8.66.[13] The WISE team also published several alternative mean-diameters of (102.25±33.63 km), (106.289±1.633 km), (123.69±43.48 km), (125.664±33.78 km) and (139.146±33.78 km), with a corresponding albedo of (0.04±0.02), (0.0537±0.0138), (0.03±0.02), (0.0327±0.0263), and (0.027±0.013).[6][13]

On 28 March 2007, an asteroid occultation of Faïna gave a best-fit ellipse dimension of (132.0 km × 88.2 km) with a quality rating of 2, indicating its irregular, elongated shape. Another occultation on 21 October 2012, gave an ellipse of (125.0 km × 125.0 km). These timed observations are taken when the asteroid passes in front of a distant star.[6]

References edit

  1. ^ a b c d e "751 Faina (A913 HE)". Minor Planet Center. Retrieved 4 June 2020.
  2. ^ a b c Schmadel, Lutz D. (2007). "(751) Faïna". Dictionary of Minor Planet Names. Springer Berlin Heidelberg. p. 71. doi:10.1007/978-3-540-29925-7_752. ISBN 978-3-540-00238-3.
  3. ^ a b c d e f g h i "JPL Small-Body Database Browser: 751 Faina (A913 HE)" (2020-04-28 last obs.). Jet Propulsion Laboratory. Retrieved 4 June 2020.
  4. ^ a b c Zappalà, V.; Bendjoya, Ph.; Cellino, A.; Farinella, P.; Froeschle, C. (1997). "Asteroid Dynamical Families". NASA Planetary Data System: EAR-A-5-DDR-FAMILY-V4.1. Retrieved 4 June 2020.} (PDS main page)
  5. ^ a b "Asteroid 751 Faina – Proper Elements". AstDyS-2, Asteroids – Dynamic Site. Retrieved 4 June 2020.
  6. ^ a b c d e f "Asteroid 751 Faina". Small Bodies Data Ferret. Retrieved 4 June 2020.
  7. ^ 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. (online, AcuA catalog p. 153)
  8. ^ 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. 12: IRAS-A-FPA-3-RDR-IMPS-V6.0. Bibcode:2004PDSS...12.....T. Retrieved 4 June 2020.
  9. ^ a b c d Mainzer, A. K.; Bauer, J. M.; Cutri, R. M.; Grav, T.; Kramer, E. A.; Masiero, J. R.; et al. (June 2016). "NEOWISE Diameters and Albedos V1.0". NASA Planetary Data System. Bibcode:2016PDSS..247.....M. Retrieved 4 June 2020.
  10. ^ a b Masiero, Joseph R.; Grav, T.; Mainzer, A. K.; Nugent, C. R.; Bauer, J. M.; Stevenson, R.; et al. (August 2014). "Main-belt Asteroids with WISE/NEOWISE: Near-infrared Albedos". The Astrophysical Journal. 791 (2): 11. arXiv:1406.6645. Bibcode:2014ApJ...791..121M. doi:10.1088/0004-637X/791/2/121. S2CID 119293330.
  11. ^ a b Carry, B. (December 2012), "Density of asteroids", Planetary and Space Science, 73 (1): 98–118, arXiv:1203.4336, Bibcode:2012P&SS...73...98C, doi:10.1016/j.pss.2012.03.009, S2CID 119226456 See Table 1.
  12. ^ a b Miles, R. (September 1989). "The Rotation Period and Phase Relation of the Asteroid 751 Faina" (PDF). Minor Planet Bulletin. 16 (1): 25. Bibcode:1989MPBu...16...25M.
  13. ^ a b c d "LCDB Data for (751) Faïna". Asteroid Lightcurve Database (LCDB). Retrieved 4 June 2020.
  14. ^ Schmadel, Lutz D. (1997). Dictionary of Minor Planet Names – Introduction, Source of Information. Springer Berlin Heidelberg. p. 16. ISBN 978-3-662-06617-1. Retrieved 18 May 2016.
  15. ^ Behrend, Raoul. "Asteroids and comets rotation curves – (751) Faïna". Geneva Observatory. Retrieved 4 June 2020.

External links edit