89 Julia

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89 Julia
89Julia (Lightcurve Inversion).png
A three-dimensional model of 89 Julia based on its light curve.
Discovery
Discovered by Édouard Stephan
Discovery date August 6, 1866
Designations
Minor planet category Main belt
Orbital characteristics[1]
Epoch December 31, 2006 (JD 2454100.5)
Aphelion 451.576 Gm (3.019 AU)
Perihelion 311.336 Gm (2.081 AU)
381.456 Gm (2.550 AU)
Eccentricity 0.184
1487.227 d (4.07 a)
18.49 km/s
129.159°
Inclination 16.142°
311.648°
44.990°
Physical characteristics
Dimensions 147.57 ± 8.32[2] km
Mass (6.71 ± 1.82) × 1018[2] kg
Mean density
3.98 ± 1.27[2] g/cm3
0.0423 m/s²
0.0801 km/s
11.387 ± 0.002[3] h
Albedo 0.176 (geometric[4]
Temperature ~174 K
Spectral type
S
8.74[5] to 12.61
6.60
0.18" to 0.052"

89 Julia is a large main-belt asteroid that was discovered by French astronomer Édouard Stephan on August 6, 1866. This was first of his two asteroid discoveries; the other was 91 Aegina. 89 Julia is believed to be named after Saint Julia of Corsica. A stellar occultation by Julia was observed on December 20, 1985.

The spectrum of 89 Julia shows the signature of silicate rich minerals with possible indications of an abundant calcic clinopyroxene component. It is classified as an S-type asteroid.[3]

References[edit]

  1. ^ Yeomans, Donald K., "89 Julia", JPL Small-Body Database Browser (NASA Jet Propulsion Laboratory), retrieved 2013-03-30. 
  2. ^ 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.
  3. ^ a b Birlan, Mirel et al. (April 2004), "Near-IR spectroscopy of asteroids 21 Lutetia, 89 Julia, 140 Siwa, 2181 Fogelin and 5480 (1989YK8), potential targets for the Rosetta mission; remote observations campaign on IRTF", New Astronomy 9 (5): 343-351, arXiv:astro-ph/0312638, Bibcode:2004NewA....9..343B, doi:10.1016/j.newast.2003.12.005. 
  4. ^ Asteroid Data Sets
  5. ^ "AstDys (89) Julia Ephemerides". Department of Mathematics, University of Pisa, Italy. Retrieved 2010-06-27. 

External links[edit]