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1337 Gerarda

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1337 Gerarda
Modelled shape of Gerarda from its lightcurve
Discovery[1]
Discovered byH. van Gent
Discovery siteJohannesburg Obs.
Discovery date9 September 1934
Designations
(1337) Gerarda
Named after
Gerarda Prins[2]
(wife of astronomer)
1934 RA1 · 1942 EE1
main-belt · (outer)[3]
background[4]
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 0
Observation arc83.06 yr (30,337 days)
Aphelion3.1978 AU
Perihelion2.6247 AU
2.9113 AU
Eccentricity0.0984
4.97 yr (1,814 days)
257.78°
0° 11m 54.24s / day
Inclination17.979°
160.29°
201.86°
Physical characteristics
Dimensions35.56±11.35 km[5]
38.84 km (derived)[3]
38.86±3.6 km[6]
40.875±0.305 km[7]
40.91±0.49 km[8]
41.53±0.48 km[9]
43.22±12.45 km[10]
46.464±0.379 km[11]
12.462±0.0145 h[12]
12.52 h[13]
0.0297±0.0042[11]
0.03±0.02[10]
0.034±0.007[9]
0.04±0.04[5]
0.042±0.001[8]
0.0425 (derived)[3]
0.0441±0.010[6]
P[11] · X[14]
C (assumed)[3]
10.88±0.45[14] · 10.970±0.001 (R)[12] · 11.06[6][8] · 11.10[3][11][13] · 11.20[1][9][10] · 11.29[5]

1337 Gerarda, provisional designation 1934 RA1, is a dark background asteroid from the outer regions of the asteroid belt, approximately 40 kilometers in diameter. It was discovered on 9 September 1934, by Dutch astronomer Hendrik van Gent at the Union Observatory in Johannesburg, South Africa.[15] The asteroid was named after Gerarda Prins, the wife of an orbit computer at Leiden Observatory.[2]

Orbit and classification

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Gerarda is a non-family asteroid from the main belt's background population.[4] It orbits the Sun in the outer main-belt at a distance of 2.6–3.2 AU once every 4 years and 12 months (1,814 days; semi-major axis of 2.91 AU). Its orbit has an eccentricity of 0.10 and an inclination of 18° with respect to the ecliptic.[1]

The body's observation arc begins with its official discovery observation at Johannesburg.[15]

Physical characteristics

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Gerarda has been characterized as a dark and primitive P-type asteroid by the Wide-field Infrared Survey Explorer (WISE).[11] It has also been classified as an X-type asteroid by Pan-STARRS photometric survey,[14] while the Collaborative Asteroid Lightcurve Link (CALL) assumes it to be a carbonaceous C-type asteroid.[3]

Rotation period

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In November 1984, a first rotational lightcurve of Gerarda was obtained from photometric observations by American astronomer Richard Binzel. Lightcurve analysis gave a rotation period of 12.52 hours with a brightness variation of 0.23 magnitude (U=2).[13] A similar period of 12.462 with an identical amplitude of 0.23 was measured by astronomers at the Palomar Transient Factory in June 2012 (U=2).[12]

Diameter and albedo

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According to the surveys carried out by the Infrared Astronomical Satellite IRAS, the Japanese Akari satellite and the NEOWISE mission of NASA's WISE telescope, Gerarda measures between 35.56 and 46.464 kilometers in diameter and its surface has an albedo between 0.0297 and 0.0441.[5][6][7][8][9][10][11]

CALL derives an albedo of 0.0425 and a diameter of 38.84 kilometers based on an absolute magnitude of 11.10.[3]

Naming

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This minor planet was named by Dutch astronomer Gerrit Pels, who computed this asteroid's orbit. It was named after Gerarda Prins, the wife of G. Prins, an orbit computer at Leiden Observatory.[2] The author of the Dictionary of Minor Planet Names, Lutz Schmadel, learned about the naming circumstances from Ingrid van Houten-Groeneveld, who was herself a long-time staff member at the Leiden Observatory.[2]

References

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  1. ^ a b c d "JPL Small-Body Database Browser: 1337 Gerarda (1934 RA1)" (2017-09-30 last obs.). Jet Propulsion Laboratory. Retrieved 28 November 2017.
  2. ^ a b c d Schmadel, Lutz D. (2007). "(1337) Gerarda". Dictionary of Minor Planet Names – (1337) Gerarda. Springer Berlin Heidelberg. p. 109. doi:10.1007/978-3-540-29925-7_1338. ISBN 978-3-540-00238-3.
  3. ^ a b c d e f g "LCDB Data for (1337) Gerarda". Asteroid Lightcurve Database (LCDB). Retrieved 28 November 2017.
  4. ^ a b "Asteroid 1337 Gerarda – Proper Elements". AstDyS-2, Asteroids – Dynamic Site. Retrieved 29 October 2019.
  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 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 22 October 2019.
  7. ^ 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.
  8. ^ 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)
  9. ^ a b c d Masiero, Joseph R.; Mainzer, A. K.; Grav, T.; Bauer, J. M.; Cutri, R. M.; Nugent, C.; et al. (November 2012). "Preliminary Analysis of WISE/NEOWISE 3-Band Cryogenic and Post-cryogenic Observations of Main Belt Asteroids". The Astrophysical Journal Letters. 759 (1): 5. arXiv:1209.5794. Bibcode:2012ApJ...759L...8M. doi:10.1088/2041-8205/759/1/L8. S2CID 46350317. Retrieved 28 November 2017.
  10. ^ a b c d Nugent, C. R.; Mainzer, A.; Masiero, J.; Bauer, J.; Cutri, R. M.; Grav, T.; et al. (December 2015). "NEOWISE Reactivation Mission Year One: Preliminary Asteroid Diameters and Albedos". The Astrophysical Journal. 814 (2): 13. arXiv:1509.02522. Bibcode:2015ApJ...814..117N. doi:10.1088/0004-637X/814/2/117. S2CID 9341381. Retrieved 28 November 2017.
  11. ^ a b c d e f 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.
  12. ^ a b c Waszczak, Adam; Chang, Chan-Kao; Ofek, Eran O.; Laher, Russ; Masci, Frank; Levitan, David; et al. (September 2015). "Asteroid Light Curves from the Palomar Transient Factory Survey: Rotation Periods and Phase Functions from Sparse Photometry". The Astronomical Journal. 150 (3): 35. arXiv:1504.04041. Bibcode:2015AJ....150...75W. doi:10.1088/0004-6256/150/3/75. S2CID 8342929. Retrieved 28 November 2017.
  13. ^ a b c Binzel, R. P. (October 1987). "A photoelectric survey of 130 asteroids". Icarus. 72 (1): 135–208. Bibcode:1987Icar...72..135B. doi:10.1016/0019-1035(87)90125-4. ISSN 0019-1035. Retrieved 28 November 2017.
  14. ^ a b c Veres, Peter; Jedicke, Robert; Fitzsimmons, Alan; Denneau, Larry; Granvik, Mikael; Bolin, Bryce; et al. (November 2015). "Absolute magnitudes and slope parameters for 250,000 asteroids observed by Pan-STARRS PS1 - Preliminary results". Icarus. 261: 34–47. arXiv:1506.00762. Bibcode:2015Icar..261...34V. doi:10.1016/j.icarus.2015.08.007. S2CID 53493339. Retrieved 28 November 2017.
  15. ^ a b "1337 Gerarda (1934 RA1)". Minor Planet Center. Retrieved 28 November 2017.
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