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JPL Small-Body Database Browser
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12238 Actor (1987 YU1)
Classification: Jupiter Trojan          SPK-ID: 2012238
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ]

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For accurate long-term ephemerides, please instead use our Horizons system.This orbit viewer was implemented using two-body methods, and hence should not be used for determining accurate long-term trajectories (over several years or decades) or planetary encounter circumstances.

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Orbital Elements at Epoch 2459000.5 (2020-May-31.0) TDB
Reference: JPL 25 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .1244827750906242 6.4694e-08  
a 5.172957829026711 1.0437e-07 au
q 4.529013683042695 3.9788e-07 au
i 21.08970135817614 5.4003e-06 deg
node 227.5674976464248 1.6931e-05 deg
peri 177.5511176511443 3.0444e-05 deg
M 312.4716670934052 2.8424e-05 deg
tp 2459567.857649120531
0.0003459 TDB
period 4297.410432736861
n .0837713794469311 2.5353e-09 deg/d
Q 5.816901975010726 1.1736e-07 au
  Orbit Determination Parameters
   # obs. used (total)      1212  
   data-arc span      12090 days (33.10 yr)  
   first obs. used      1986-11-30  
   last obs. used      2020-01-06  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-N16  
   condition code      0  
   norm. resid. RMS      .50282  
   source      ORB  
   producer      Otto Matic  
   solution date      2020-Jan-28 22:45:28  

Additional Information
 Earth MOID = 3.53875 au 
 Jupiter MOID = .406829 au 
 T_jup = 2.852 
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Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ]

Physical Parameter Table
Parameter Symbol Value Units Sigma Reference Notes
absolute magnitude H 10.9   n/a MPO365397  
diameter diameter 30.252 km 4.843 urn:nasa:pds:neowise_diameters_albedos::2.0[jupiter_trojans] (  
rotation period rot_per 7.284 h n/a LCDB (Rev. 2019-August); Warner et al., 2009 Result based on less than full coverage, so that the period may be wrong by 30 percent or so.
Published Reference List:
[Duffard, R. Melita, M.; Ortiz, J.; Licandro, J.; et al. (2008) ACM 2008, 8187.]
[Melita, M.D.; Duffard, R.; Williams, I.P.; Jones, D.C.; et al. (2010) Planet. Space Sci. 58, 1035-1039.]
[Ryan, E.L.; Sharkey, B.N.L.; Woodward, C.E. (2017) Astron. J. 153, A116.]
[Szabo, Gy.M.; Pal, A.; Kiss, Cs.; Kiss, L.L.; et al. (2017) Astron. Astrophys. 599, A44.]
geometric albedo albedo 0.092   0.017 urn:nasa:pds:neowise_diameters_albedos::2.0[jupiter_trojans] (  

12238 Actor           Discovered 1987 Dec. 17 by E. W. Elst and G. Pizarro at the European Southern Observatory.
Actor was the alleged father of Cteatos and Eurytos, two Greek warriors who beat Nestor in the chariot race.
NOTE: some special characters may not display properly (any characters within {} are an attempt to place the proper accent above a character)
Reference: 20030106/MPCPages.arcLast Updated: 2003-10-02

Alternate Designations
 1987 YU1 = 1986 WW8 
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ]
FirstGov 2020-Apr-05 17:29 UT
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