1382 Gerti

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1382 Gerti
1382Gerti (Lightcurve Inversion).png
Lightcurve-based 3D-model of Gerti
Discovery [1]
Discovered by K. Reinmuth
Discovery site Heidelberg Obs.
Discovery date 21 January 1925
Designations
MPC designation (1382) Gerti
Named after
Gertrud Höhne [2]
(ARI secretary)
1925 BB · 1929 LH
1933 UL1 · 1936 QB1
main-belt · (inner)
Flora[3] · background [4]
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 0
Observation arc 92.18 yr (33,670 days)
Aphelion 2.5119 AU
Perihelion 1.9274 AU
2.2196 AU
Eccentricity 0.1317
3.31 yr (1,208 days)
258.61°
0° 17m 52.8s / day
Inclination 1.5621°
353.04°
246.96°
Physical characteristics
Dimensions 8.54 km (derived)[3]
9.14±0.95 km[5]
9.75±1.68 km[6]
11.94±0.19 km[7]
3.0±0.2 h[8]
3.081545±0.000005 h[9]
3.082±0.0004 h[10]
3.082±0.002 h[11]
0.196±0.024[7]
0.24 (assumed)[3]
0.278±0.059[5]
0.28±0.08[6]
S (assumed)[3]
11.765±0.000 (R)[10] · 12.00[1][7] · 12.04±0.28[12] · 12.20[5] · 12.27[6] · 12.51[3] · 12.51±0.01[11][13]

1382 Gerti, provisional designation 1925 BB, is a Florian asteroid from the inner regions of the asteroid belt, approximately 10 kilometers in diameter. It was discovered on 21 January 1925, by astronomer Karl Reinmuth at the Heidelberg-Königstuhl State Observatory in southwest Germany.[14] The asteroid was named after a secretary of the Astronomical Calculation Institute, Gertrud Höhne.

Orbit and classification[edit]

Gerti has been dynamically classified as a member of the Flora family (402), a giant asteroid family and the largest family of stony asteroids in the main-belt.[3] It is, however, a non-family asteroid of the main belt's background population when applying the Hierarchical Clustering Method to its proper orbital elements.[4]

It orbits the Sun in the inner main-belt at a distance of 1.9–2.5 AU once every 3 years and 4 months (1,208 days). Its orbit has an eccentricity of 0.13 and an inclination of 2° with respect to the ecliptic.[1] The body's observation arc begins with its official discovery observation at Heidelberg in January 1925.[14]

Physical characteristics[edit]

The LCDB assumes it to be a stony S-type asteroid, due to its dynamical classification as a member of the Flora family (402).[3]

Rotation period[edit]

Two rotational lightcurve of Gerti were obtained from photometric observations by Wiesław Wiśniewski in February 1988, and by astronomers at the Palomar Transient Factory in January 2011, respectively. Lightcurve analysis gave an identical rotation period of 3.082 hours with a respective brightness amplitude of 0.20 and 0.29 magnitude (U=3/2).[10][11] A third lightcurve by René Roy in March 2008 gave a period of 3.0 hours with an amplitude of 0.36 magnitude (U=2).[8]

Poles[edit]

In 2011, a modeled lightcurve using data from the Uppsala Asteroid Photometric Catalogue and other sources gave a concurring sidereal period of 3.081545 hours, as well as two spin axis of (268.0°, 23.0°) and (87.0°, 28.0°) in ecliptic coordinates (λ, β).[9]

Diameter and albedo[edit]

According to the surveys carried out by the Japanese Akari satellite and the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Gerti measures between 9.14 and 11.94 kilometers in diameter and its surface has an albedo between 0.196 and 0.28.[5][6][7]

The Collaborative Asteroid Lightcurve Link assumes an albedo of 0.24 – taken from 8 Flora, the Flora family's parent body – and derives a diameter of 8.54 kilometers based on an absolute magnitude of 12.51.[3]

Naming[edit]

This minor planet was named after Gertrud Höhne who was a secretary at the Berlin Astronomical Calculation Institute (German: Astronomisches Rechen-Institut. The official naming citation was mentioned in The Names of the Minor Planets by Paul Herget in 1955 (H 125).[2]

References[edit]

  1. ^ a b c d "JPL Small-Body Database Browser: 1382 Gerti (1925 BB)" (2017-03-29 last obs.). Jet Propulsion Laboratory. Retrieved 27 October 2017.
  2. ^ a b Schmadel, Lutz D. (2007). Dictionary of Minor Planet Names – (1382) Gerti. Springer Berlin Heidelberg. p. 112. ISBN 978-3-540-00238-3. Retrieved 27 October 2017.
  3. ^ a b c d e f g h "LCDB Data for (1382) Gerti". Asteroid Lightcurve Database (LCDB). Retrieved 27 October 2017.
  4. ^ a b "Small Bodies Data Ferret". Nesvorny HCM Asteroid Families V3.0. Retrieved 27 October 2017.
  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 27 October 2017.
  6. ^ 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. Retrieved 27 October 2017.
  7. ^ 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. Retrieved 27 October 2017.
  8. ^ a b Behrend, Raoul. "Asteroids and comets rotation curves – (1382) Gerti". Geneva Observatory. Retrieved 27 October 2017.
  9. ^ a b 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 27 October 2017.
  10. ^ 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. Retrieved 27 October 2017.
  11. ^ a b c Wisniewski, W. Z.; Michalowski, T. M.; Harris, A. W.; McMillan, R. S. (March 1995). "Photoelectric Observations of 125 Asteroids". Abstracts of the Lunar and Planetary Science Conference. Bibcode:1995LPI....26.1511W. Retrieved 27 October 2017.
  12. ^ 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. Retrieved 27 October 2017.
  13. ^ 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 27 October 2017.
  14. ^ a b "1382 Gerti (1925 BB)". Minor Planet Center. Retrieved 27 October 2017.

External links[edit]