1184 Gaea

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1184 Gaea
Discovery [1]
Discovered by K. Reinmuth
Discovery site Heidelberg Obs.
Discovery date 5 September 1926
Designations
MPC designation (1184) Gaea
Named after
Gaea (Gaia) [2]
(Greek mythology)
1926 RE · 1930 OE
1931 XG
main-belt · (middle)[3]
Aeria[4]
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 0
Observation arc 91.06 yr (33,260 days)
Aphelion 2.8555 AU
Perihelion 2.4804 AU
2.6680 AU
Eccentricity 0.0703
4.36 yr (1,592 days)
0.0836°
0° 13m 34.32s / day
Inclination 11.315°
355.75°
311.34°
Physical characteristics
Dimensions 11.783±0.296 km[5]
12.048±0.146 km[6]
26.52 km (calculated)[3]
2.94±0.06 h[7]
0.10 (assumed)[3][a]
0.4512±0.0298[6]
0.462±0.061[5]
S/C (assumed)[3][a]
11.0[1][3] · 11.1[6] · 11.42±0.31[8]

1184 Gaea, provisional designation 1926 RE, is an Aerian asteroid from the central regions of the asteroid belt, approximately 20 kilometers in diameter. It was discovered on 5 September 1926, by astronomer Karl Reinmuth at the Heidelberg-Königstuhl State Observatory in southwest Germany.[9] The asteroid was named after the goddess of Earth, Gaea (Gaia), from Greek mythology.[2]

Orbit and classification[edit]

Gaea is a member of the small Aeria family (539),[4] named after its parent body 369 Aeria.[10]:23 It orbits the Sun in the central main-belt at a distance of 2.5–2.9 AU once every 4 years and 4 months (1,592 days). Its orbit has an eccentricity of 0.07 and an inclination of 11° with respect to the ecliptic.[1]

The body's observation arc begins at Heidelberg in November 1925, more than 2 months after its official discovery observation.[9]

Physical characteristics[edit]

The asteroid's spectral type is unknown, the LCDB assumes a stony (S) or carbonaceous (C) composition to be equally likely,[a] while the overall spectral type for members of the Aeria family is that of an X-type.[10]:23 The high albedo figures obtained from observations with the WISE telescope do not agree with neither of these spectral types (see below).[6]

Rotation period[edit]

In January 2011, a rotational lightcurve of Gaea was obtained from photometric observations by French amateur astronomer René Roy. Lightcurve analysis gave a short rotation period of 2.94 hours with a brightness amplitude of 0.09 magnitude (U=2).[7] A low brightness amplitude also indicates that the body might have a spheroidal rather than an irregular shape.

Diameter and albedo[edit]

According to the survey carried out by the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Gaea measures 11.783 and 12.048 kilometers in diameter and its surface has a high albedo of 0.462 and 0.4512, respectively.[5][6]

The Collaborative Asteroid Lightcurve Link assumes an albedo of 0.10 – a compromise value between the stony (0.20) and carbonaceous (0.057) asteroids, both found abundantly in this region of the asteroid belt – and consequently calculates a much larger diameter of 26.52 kilometers based on an absolute magnitude of 11.0.[3]

Naming[edit]

This minor planet was named after Gaia (or Gaea), the goddess of Earth in Greek mythology, her son and husband was Uranus, the god of the sky. Uranus and Gaia were the parents of the first generation of Titans (six males and six females), and the ancestors of most of the Greek gods, the asteroid's name was proposed by German ARI-astronomer Gustav Stracke after whom the asteroid 1019 Strackea was named.[2]

Notes[edit]

  1. ^ a b c Generic stony/carbonaceous composition with a compromise albedo of 0.10, for asteroids with an semi-major axis of 2.6–2.7 AU, according to LCDB's – 2. Taxonomic Class, orbital class, and albedo

References[edit]

  1. ^ a b c d "JPL Small-Body Database Browser: 1184 Gaea (1926 RE)" (2017-09-27 last obs.). Jet Propulsion Laboratory. Retrieved 24 October 2017. 
  2. ^ a b c Schmadel, Lutz D. (2007). Dictionary of Minor Planet Names – (1184) Gaea. Springer Berlin Heidelberg. p. 99. ISBN 978-3-540-00238-3. Retrieved 24 October 2017. 
  3. ^ a b c d e f "LCDB Data for (1184) Gaea". Asteroid Lightcurve Database (LCDB). Retrieved 24 October 2017. 
  4. ^ a b "Small Bodies Data Ferret". Nesvorny HCM Asteroid Families V3.0. Retrieved 24 October 2017. 
  5. ^ 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:1406.6645Freely accessible. Bibcode:2014ApJ...791..121M. doi:10.1088/0004-637X/791/2/121. Retrieved 24 October 2017. 
  6. ^ a b c d e Mainzer, A.; Grav, T.; Masiero, J.; Hand, E.; Bauer, J.; Tholen, D.; et al. (November 2011). "NEOWISE Studies of Spectrophotometrically Classified Asteroids: Preliminary Results" (PDF). The Astrophysical Journal. 741 (2): 25. arXiv:1109.6407Freely accessible. Bibcode:2011ApJ...741...90M. doi:10.1088/0004-637X/741/2/90. Retrieved 24 October 2017. 
  7. ^ a b Behrend, Raoul. "Asteroids and comets rotation curves – (1184) Gaea". Geneva Observatory. Retrieved 24 October 2017. 
  8. ^ 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:1506.00762Freely accessible. Bibcode:2015Icar..261...34V. doi:10.1016/j.icarus.2015.08.007. Retrieved 24 October 2017. 
  9. ^ a b "1184 Gaea (1926 RE)". Minor Planet Center. Retrieved 24 October 2017. 
  10. ^ a b Nesvorný, D.; Broz, M.; Carruba, V. (December 2014). "Identification and Dynamical Properties of Asteroid Families" (PDF). Asteroids IV: 297–321. arXiv:1502.01628Freely accessible. Bibcode:2015aste.book..297N. doi:10.2458/azu_uapress_9780816532131-ch016. Retrieved 24 October 2017. 

External links[edit]