42 Isis

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42 Isis
42Isis (Lightcurve Inversion).png
A three-dimensional model of 42 Isis based on its light curve.
Discovery
Discovered by Norman Robert Pogson
Discovery date May 23, 1856
Designations
Named after
Isis
Minor planet category Main belt
Adjectives Isidian
Orbital characteristics
Epoch December 31, 2006 (JD 2454100.5)
Aphelion 446.706 Gm (2.986 AU)
Perihelion 283.890 Gm (1.898 AU)
365.298 Gm (2.442 AU)
Eccentricity 0.223
1393.737 d (3.82 a)
18.82 km/s
121.874°
Inclination 8.530°
84.398°
236.626°
Physical characteristics
Dimensions 102.73 ± 2.73[1] km
Mass (1.58 ± 0.52) × 1018[1] kg
Mean density
2.78 ± 0.93[1] g/cm3
0.0280 m/s²
0.0530 km/s
Albedo 0.171 (geometric)[2]
Temperature ~178 K
Spectral type
S
9.18[3] to 13.50
7.53

42 Isis /ˈsɨs/ is a large main-belt asteroid, measuring 100.2 km in diameter. It was discovered by N.R. Pogson on May 23, 1856, at Oxford. It was Pogson's first asteroid discovery.

The asteroid's name was chosen by Manuel John Johnson, director of the Radcliffe Observatory in Oxford. Although Isis is the name of an Egyptian goddess, the name was chosen in homage to Pogson's astronomer daughter, (Elizabeth) Isis Pogson.[4] In addition, the Isis is the stretch of the River Thames that runs through Oxford.[5]

The light curve inversion technique, when applied to photometric observations of this asteroid, show multiple local irregularities. The overall shape displays little elongation, with a ratio between the major and minor axes equal to 1.1. The measured rotation period for this model is 13.59701 hours.[6] The spectrum of 42 Isis reveals the strong presence of the mineral Olivine, a relatively rarity in the asteroid belt.[7]

References[edit]

  1. ^ a b c Carry, B. (December 2012), "Density of asteroids", Planetary and Space Science 73: 98–118, arXiv:1203.4336, Bibcode:2012P&SS...73...98C, doi:10.1016/j.pss.2012.03.009.  See Table 1.
  2. ^ Asteroid Data Sets
  3. ^ "AstDys (42) Isis Ephemerides". Department of Mathematics, University of Pisa, Italy. Retrieved 2010-06-27. 
  4. ^ Bruck, Mary (2009), Women in Early British and Irish Astronomy, Springer, p. 157, ISBN 978-90-481-2472-5. 
  5. ^ Lutz D. Schmadel, Dictionary of Minor Planet Names: Addendum to Fifth Edition: 2006 - 2008.
  6. ^ Torppa, Johanna et al. (August 2003), "Shapes and rotational properties of thirty asteroids from photometric data", Icarus 164 (2): 346–383, Bibcode:2003Icar..164..346T, doi:10.1016/S0019-1035(03)00146-5. 
  7. ^ Burbine, T. H. et al. (July 2000), "The Nature of Olivine Asteroids", Meteoritics & Planetary Science 35: A35, Bibcode:2000M&PSA..35R..35B. 

External links[edit]