998 Bodea

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998 Bodea
Modelled shape of Bodea from its lightcurve
Discovery [1]
Discovered byK. Reinmuth
Discovery siteHeidelberg Obs.
Discovery date6 August 1923
Designations
(998) Bodea
Pronunciation/ˈbdiə/
Named after
Johann Elert Bode
(German astronomer)[2]
A923 PC · 1967 PA
1923 NU
Orbital characteristics[3]
Epoch 27 April 2019 (JD 2458600.5)
Uncertainty parameter 0
Observation arc96.34 yr (35,187 d)
Aphelion3.7826 AU
Perihelion2.4547 AU
3.1187 AU
Eccentricity0.2129
5.51 yr (2,012 d)
89.259°
0° 10m 44.4s / day
Inclination15.505°
301.18°
72.139°
Physical characteristics
Mean diameter
  • 31.21±0.39 km[7]
  • 31.761±0.497 km[8]
  • 38.16±3.1 km[9]
8.574 h[10][a]
(7.0°, −59.0°) (λ/β)[5][11]
  • 0.0211±0.004[9]
  • 0.030±0.001[8]
  • 0.033±0.001[7]
C (assumed)[12]
11.5[1][3]

998 Bodea (prov. designation: A923 PC or 1923 NU) is a dark background asteroid from the outer regions of the asteroid belt, approximately 32 kilometers (20 miles) in diameter. It was discovered on 6 August 1923, by astronomer Karl Reinmuth at the Heidelberg Observatory in southern Germany.[1] The presumed C-type asteroid with an irregular shape has a rotation period of 8.6 hours. It was named after German astronomer Johann Elert Bode (1747–1826).

Orbit and classification[edit]

Bodea is a non-family asteroid of the main belt's background population when applying the hierarchical clustering method to its proper orbital elements.[4][5][6] It orbits the Sun in the outer asteroid belt at a distance of 2.5–3.8 AU once every 5 years and 6 months (2,012 days; semi-major axis of 3.12 AU). Its orbit has an eccentricity of 0.21 and an inclination of 16° with respect to the ecliptic.[3] The body's observation arc begins at Heidelberg on 8 August 1923, just two days after its official discovery observation.[1]

Naming[edit]

This minor planet was named after Johann Elert Bode (1747–1826), German astronomer, author of the Berliner Astronomisches Jahrbuch, known for the empirical Titius–Bode law about the sequence of planetary distances. Bode also was the director of the Berlin Observatory in 1780. The asteroid's name was proposed by Swedish astronomer Bror Asplind (see citation for 958 Asplinda). The official naming citation was mentioned in The Names of the Minor Planets by Paul Herget in 1955 (H 95). The lunar crater Bode is also named in his honor.[2]

Physical characteristics[edit]

Bodea is an assumed C-type asteroid.[12] Due to its very low albedo of 0.03 or less, it could also be a P- or D-type asteroid which are very common in the outer asteroid belt and among the Jupiter trojan population.

Rotation period[edit]

Lightcurve-based 3D-model of Bodea

In September 2006, a rotational lightcurve of Bodea was obtained from photometric observations by Italian astronomers Roberto Crippa and Federico Manzini at the Sozzago Astronomical Station (A12). Lightcurve analysis gave a well defined rotation period of 8.574±0.001 hours with a relatively high brightness amplitude of 0.68±0.01 magnitude (U=3), which is indicative of an elongated, irregular shape.[10][12][a]

Poles[edit]

Modeled photometric data from the Lowell Photometric Database (LPD) and WISE thermal data, gave a concurring sidereal rotation period of 8.57412 hours. Each modeled lightcurve also determined the object's spin axes. Durech gives only one pole, namely (7.0°, −59.0°), while Hanus determined two lower rated poles at (336.0°, −70.0°) and (72.0°, −56.0°) in ecliptic coordinates (λ, β).[5][11][13]

Diameter and albedo[edit]

According to the survey carried out by the NEOWISE mission of NASA's WISE telescope, Bodea measures 31.761±0.497 kilometers in diameter and its surface has an albedo of 0.030±0.001.[8] Results from the Japanese Akari satellite are in agreement with 31.21±0.39 km and an albedo of 0.030±0.001.[7] Only the Infrared Astronomical Satellite IRAS gave a larger diameter of 38.16±3.1 km and, correspondingly, a lower albedo of 0.0211±0.004.[9] The Collaborative Asteroid Lightcurve Link adopts an albedo of 0.0304 and derives a diameter of 38.23 kilometers based on an absolute magnitude of 11.5.[12]

Notes[edit]

  1. ^ a b Lightcurve plot (998) Bodea, by Roberto Crippa and Federico Manzini at the Sozzago Astronomical Station (A12). The obtained rotation period was 8.574 hours (0.357 days). Summary figures at Raoul Behrend – Geneva Observatory.

References[edit]

  1. ^ a b c d e "998 Bodea (A923 PC)". Minor Planet Center. Retrieved 21 January 2020.
  2. ^ a b Schmadel, Lutz D. (2007). "(998) Bodea". Dictionary of Minor Planet Names. Springer Berlin Heidelberg. p. 86. doi:10.1007/978-3-540-29925-7_999. ISBN 978-3-540-00238-3.
  3. ^ a b c d "JPL Small-Body Database Browser: 998 Bodea (A923 PC)" (2019-12-07 last obs.). Jet Propulsion Laboratory. Retrieved 21 January 2020.
  4. ^ a b "Asteroid 998 Bodea – Proper Elements". AstDyS-2, Asteroids – Dynamic Site. Retrieved 21 January 2020.
  5. ^ a b c d "Asteroid 998 Bodea". Small Bodies Data Ferret. Retrieved 21 January 2020.
  6. ^ a b 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 2 April 2020. (PDS main page)
  7. ^ a b c 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 Masiero, Joseph R.; Mainzer, A. K.; Grav, T.; Bauer, J. M.; Cutri, R. M.; Dailey, J.; et al. (November 2011). "Main Belt Asteroids with WISE/NEOWISE. I. Preliminary Albedos and Diameters". The Astrophysical Journal. 741 (2): 20. arXiv:1109.4096. Bibcode:2011ApJ...741...68M. doi:10.1088/0004-637X/741/2/68. Retrieved 21 January 2020.
  9. ^ a b c 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 21 January 2020.
  10. ^ a b Behrend, Raoul. "Asteroids and comets rotation curves – (998) Bodea". Geneva Observatory. Retrieved 21 January 2020.
  11. ^ a b Ďurech, J.; Hanuš, J.; Oszkiewicz, D.; Vančo, R. (March 2016). "Asteroid models from the Lowell photometric database". Astronomy and Astrophysics. 587: A48. arXiv:1601.02909. Bibcode:2016A&A...587A..48D. doi:10.1051/0004-6361/201527573. ISSN 0004-6361.
  12. ^ a b c d "LCDB Data for (998) Bodea". Asteroid Lightcurve Database (LCDB). Retrieved 21 January 2020.
  13. ^ Hanuš, J.; Delbo, M.; Ďurech, J.; Alí-Lagoa, V. (July 2018). "Thermophysical modeling of main-belt asteroids from WISE thermal data". Icarus. 309: 297–337. arXiv:1803.06116. Bibcode:2018Icar..309..297H. doi:10.1016/j.icarus.2018.03.016. ISSN 0019-1035.

External links[edit]