130 Elektra

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130 Elektra
130Elektra (Lightcurve Inversion).png
A three-dimensional model of 130 Elektra based on its light curve.
Discovery[1]
Discovered by Christian Heinrich Friedrich Peters
Discovery date 17 February 1873
Designations
Named after
Electra
Main belt
Orbital characteristics[2][3]
Epoch 31 July 2016 (JD 2457600.5)
Uncertainty parameter 0
Observation arc 122.35 yr (44690 d)
Aphelion 3.77969 AU (565.434 Gm)
Perihelion 2.47815 AU (370.726 Gm)
3.12892 AU (468.080 Gm)
Eccentricity 0.20799
5.53 yr (2021.6 d)
16.66 km/s
128.885°
0° 10m 41.084s / day
Inclination 22.8461°
145.401°
236.231°
Known satellites S/2003 (130) 1
S/2014 (130) 1
Earth MOID 1.54388 AU (230.961 Gm)
Jupiter MOID 1.88708 AU (282.303 Gm)
Jupiter Tisserand parameter 3.061
Physical characteristics
Dimensions 182.25±11.8 km[3]
215×155 ± 12 km[4][5][6][7]
Mass 6.6±0.4×1018 kg[8]
1.28±0.10×1019 kg[9][10]
Mean density
1.3 ± 0.3 g/cm3[8]
3.8 ± 0.3 g/cm3[9]
Equatorial surface gravity
0.07 m/s2[11]
Equatorial escape velocity
0.13 km/s[11]
5.225 h (0.2177 d)
0.230103 d (5.52247 h)[12]
157°
-88°[12]
68°
0.0755±0.011[3]
0.076 ± 0.011 [5]
Surface temp. min mean max
Kelvin ~157 251
Celsius -23°
G[13]
7.12[3][5]

130 Elektra is a very large outer main-belt asteroid. It was discovered by C. H. F. Peters on February 17, 1873, and named after Electra, an avenger in Greek mythology.

Its spectrum is of the G type, hence it probably has a Ceres-like composition. Spectral signatures of organic compounds have been seen on Elektra's surface.[14]

In the late 1990s, a network of astronomers worldwide gathered lightcurve data that was ultimately used to derive the spin states and shape models of 10 new asteroids, including (130) Elektra. The light curve of (130) Elektra forms a double sinusoid while the shape model is elongated and the derived rotation axis is perpendicular to the plane of the ecliptic.[15][16]

Optical observations have found two satellites of this asteroid. Once the orbits are known, Elektra's mass can be reliably found. The value of 6.6×1018 kg indicates a density of 1.3 ± 0.3 g/cm3. Optical observations have also determined that Elektra's shape is quite irregular, as well as giving indications of albedo differences of 5-15% on its surface.[12]

Satellites S/2003 (130) 1 and S/2014 (130) 1[edit]

In 2003, a small moon of (130) Elektra was detected using the Keck II telescope. The diameter of the satellite is 4 km and it orbits at a distance of about 1170 km. The satellite has been given the provisional designation S/2003 (130) 1. Due to only a few observations to date, its orbit is still relatively loosely constrained.[9] In December 2014 a slightly smaller moon, orbiting Elektra about three times closer than S/2003 (130) 1, was discovered using the SPHERE instrument on the VLT's Melipal (UT3) telescope. This second satellite has been provisionally named S/2014 (130) 1.

S/2003 (130) 1
Discovery[17]
Discovered by W. J. Merline, P. M. Tamblyn,
C. Dumas, L. M. Close,
C. R. Chapman, and F. Menard
Discovery date 15 August 2003
Designations
Main belt
Orbital characteristics[8]
1318 ± 25 km
Eccentricity 0.13 ± 0.03
5.258 ± 0.0053 d
23 m/s
Inclination 3
Satellite of 130 Elektra
Physical characteristics
Dimensions 7 ± 3 km [12]
Mass ~4×1014 kg [18]
Equatorial escape velocity
~ 4 m/s
14.5[12]
S/2014 (130) 1
Discovery
Discovered by B. Yang, Z. Wahhaj,
M. Marsset, J. Milli,
C. Dumas, and F. Marchis
Discovery date December 6, 2014
Designations
Main belt
Orbital characteristics
460
Eccentricity ?
1.1 d
Inclination ?
Satellite of 130 Elektra
Physical characteristics
Dimensions 5.2 ± 1.2 km

Gallery[edit]

References[edit]

  1. ^ Discovery Circumstances: Numbered Minor Planets, Minor Planet Centre
  2. ^ "The Asteroid Orbital Elements Database". astorb. Lowell Observatory. 
  3. ^ a b c d "130 Elektra". JPL Small-Body Database. NASA/Jet Propulsion Laboratory. Retrieved 12 May 2016. 
  4. ^ Based in IRAS mean diameter of 182±12 km, a/b ratio of 1.4 as per the following references
  5. ^ a b c Supplemental IRAS Minor Planet Survey Archived 2010-01-17 at WebCite
  6. ^ PDS node spin vector database (in particular, the synthetic compiled value of a/b=1.4).
  7. ^ (130) Elektra and S/2003 (130) 1, at Johnston's archive (maintained by W. R. Johnston).
  8. ^ a b c Marchis, Franck; P. Descamps; J. Berthier; D. hestroffer; F. vachier; M. Baek; et al. (2008). "Main Belt Binary Asteroidal Systems With Eccentric Mutual Orbits". Icarus. 195 (1): 295–316. arXiv:0804.1385free to read. Bibcode:2008Icar..195..295M. doi:10.1016/j.icarus.2007.12.010. 
  9. ^ a b c 130 Elektra and S/2003 (130) 1, orbit data website maintained by F. Marchis.
  10. ^ Error estimate derived from consideration of and given errors in a and P. See propagation of uncertainty.
  11. ^ a b On the extremities of the long axis.
  12. ^ a b c d e F. Marchis; et al. (2006). "Shape, size and multiplicity of main-belt asteroids I. Keck Adaptive Optics survey". Icarus. 185 (1): 39–63. Bibcode:2006Icar..185...39M. doi:10.1016/j.icarus.2006.06.001. PMC 2600456free to read. PMID 19081813. 
  13. ^ PDS node taxonomy database Archived 2010-01-16 at WebCite
  14. ^ D.P. Cruikshank & R.H. Brown (1987). "Organic Matter on Asteroid 130 Elektra". Science. 238 (4824): 183–4. Bibcode:1987Sci...238..183C. doi:10.1126/science.238.4824.183. PMID 17800458. 
  15. ^ Durech, J.; et al. (April 2007), "Physical models of ten asteroids from an observers' collaboration network", Astronomy and Astrophysics, 465 (1): 331–337, Bibcode:2007A&A...465..331D, doi:10.1051/0004-6361:20066347. 
  16. ^ Durech, J.; Kaasalainen, M.; Marciniak, A.; Allen, W. H. (2007). "Asteroid brightness and geometry". Astronomy and Astrophysics. 465 (1): 331–337. Bibcode:2007A&A...465..331D. doi:10.1051/0004-6361:20066347. 
  17. ^ IAUC 8183
  18. ^ Assuming a similar density to the primary.
  19. ^ "Elektra: A New Triple Asteroid". www.eso.org. European Southern Observatory. Retrieved 9 May 2016. 

External links[edit]