1429 Pemba, provisional designation 1937 NH, is a stony background asteroid from the central regions of the asteroid belt, approximately 10 kilometers in diameter. It was discovered on 2 July 1937, by South African astronomer Cyril Jackson at the Union Observatory in Johannesburg.[11] The asteroid was named for the Pemba Island off the coast of Tanzania.[2]

1429 Pemba
Discovery[1]
Discovered byC. Jackson
Discovery siteJohannesburg Obs.
Discovery date2 July 1937
Designations
(1429) Pemba
Named after
Pemba Island[2]
(African East coast)
1937 NH · 1949 JK
main-belt · (inner)[3]
background[4]
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 0
Observation arc79.93 yr (29,193 days)
Aphelion3.4109 AU
Perihelion1.7004 AU
2.5557 AU
Eccentricity0.3347
4.09 yr (1,492 days)
207.67°
0° 14m 28.32s / day
Inclination7.7492°
47.700°
297.82°
Physical characteristics
Dimensions8.71±1.86 km[5]
9.874±0.051 km[6]
10.37 km (taken)[3]
10.371 km[7]
10.531±0.041 km[8]
10.75±0.67 km[9]
20 h[10]
0.1316[3][7]
0.154±0.021[9]
0.1598±0.0235[8]
0.19±0.11[5]
0.196±0.022[6]
S (assumed)[3]
12.4[1] · 12.50[8][9] · 12.74[3][5] · 12.74±0.2[7][10]

Orbit and classification

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Pemba is a non-family asteroid from the main belt's background population.[4] It orbits the Sun in the central main-belt at a distance of 1.7–3.4 AU once every 4 years and 1 month (1,492 days). Its orbit has an eccentricity of 0.33 and an inclination of 8° with respect to the ecliptic.[1] The body's observation arc begins with its official discovery observation at Johannesburg.[11]

Physical characteristics

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Pemba is an assumed stony S-type asteroid.[3]

Rotation period

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In September 1982, a rotational lightcurve of Pemba was obtained from photometric observations. Analysis of the fragmentary lightcurve gave a rotation period of 20 hours with a brightness amplitude of 0.3 magnitude (U=1).[10] As of 2017, no secure period has been determined.[3]

Diameter and albedo

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According to the surveys carried out by the Japanese Akari satellite and the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Pemba measures between 8.71 and 10.75 kilometers in diameter and its surface has an albedo between 0.1316 and 0.196.[5][6][7][8][9]

The Collaborative Asteroid Lightcurve Link adopts Petr Pravec's revised WISE results, that is, an albedo of 0.1316 and a diameter of 10.37 kilometers based on an absolute magnitude of 12.74.[3][7]

Naming

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This minor planet was named for the Pemba Island, Tanzania, part of the Zanzibar Archipelago, which was once under the rule of the Sultan of Zanzibar.[2] It is located off the East Coast of Africa in the Indian Ocean. The official naming citation was published by the Minor Planet Center in April 1953 (M.P.C. 909).[12]

References

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  1. ^ a b c d "JPL Small-Body Database Browser: 1429 Pemba (1937 NH)" (2017-06-05 last obs.). Jet Propulsion Laboratory. Retrieved 26 October 2017.
  2. ^ a b c Schmadel, Lutz D. (2007). "(1429) Pemba". Dictionary of Minor Planet Names – (1429) Pemba. Springer Berlin Heidelberg. p. 115. doi:10.1007/978-3-540-29925-7_1430. ISBN 978-3-540-00238-3.
  3. ^ a b c d e f g h "LCDB Data for (1429) Pemba". Asteroid Lightcurve Database (LCDB). Retrieved 26 October 2017.
  4. ^ a b "Small Bodies Data Ferret". Nesvorny HCM Asteroid Families V3.0. Archived from the original on 2 August 2017. Retrieved 26 October 2017.
  5. ^ a b c d Nugent, C. R.; Mainzer, A.; Bauer, J.; Cutri, R. M.; Kramer, E. A.; Grav, T.; et al. (September 2016). "NEOWISE Reactivation Mission Year Two: Asteroid Diameters and Albedos". The Astronomical Journal. 152 (3): 12. arXiv:1606.08923. Bibcode:2016AJ....152...63N. doi:10.3847/0004-6256/152/3/63.
  6. ^ a b c 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. Retrieved 26 October 2017.
  7. ^ a b c d e Pravec, Petr; Harris, Alan W.; Kusnirák, Peter; Galád, Adrián; Hornoch, Kamil (September 2012). "Absolute magnitudes of asteroids and a revision of asteroid albedo estimates from WISE thermal observations". Icarus. 221 (1): 365–387. Bibcode:2012Icar..221..365P. doi:10.1016/j.icarus.2012.07.026. Retrieved 26 October 2017.
  8. ^ a b c d Mainzer, A.; Grav, T.; Masiero, J.; Hand, E.; Bauer, J.; Tholen, D.; et al. (November 2011). "NEOWISE Studies of Spectrophotometrically Classified Asteroids: Preliminary Results". The Astrophysical Journal. 741 (2): 25. arXiv:1109.6407. Bibcode:2011ApJ...741...90M. doi:10.1088/0004-637X/741/2/90. S2CID 35447010.
  9. ^ 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)
  10. ^ a b c Harris, A. W.; Young, J. W.; Bowell, E.; Tholen, D. J. (November 1999). "Asteroid Lightcurve Observations from 1981 to 1983". Icarus. 142 (1): 173. Bibcode:1999Icar..142..173H. doi:10.1006/icar.1999.6181. Retrieved 26 October 2017.
  11. ^ a b "1429 Pemba (1937 NH)". Minor Planet Center. Retrieved 26 October 2017.
  12. ^ 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. Bibcode:2009dmpn.book.....S. doi:10.1007/978-3-642-01965-4. ISBN 978-3-642-01964-7.
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