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JPL Small-Body Database Browser
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201 Penelope (A879 PA)
Classification: Main-belt Asteroid          SPK-ID: 2000201
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]

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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 94 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .1792372717717131 3.0023e-08  
a 2.678166941332822 6.3871e-09 au
q 2.198139605419133 7.8455e-08 au
i 5.755872446232437 2.9393e-06 deg
node 156.9252663012895 3.5901e-05 deg
peri 180.7167832537897 3.7658e-05 deg
M 34.34804629519657 1.2656e-05 deg
tp 2458847.759420831549
5.5956e-05 TDB
period 1600.865680338037
n .2248783295322958 8.0445e-10 deg/d
Q 3.158194277246511 7.5318e-09 au
  Orbit Determination Parameters
   # obs. used (total)      2832  
   data-arc span      51263 days (140.35 yr)  
   first obs. used      1879-08-13  
   last obs. used      2019-12-20  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-N16  
   condition code      0  
   norm. resid. RMS      .4663  
   source      ORB  
   producer      Otto Matic  
   solution date      2020-Feb-22 15:20:41  

Additional Information
 Earth MOID = 1.18893 au 
 Jupiter MOID = 2.23242 au 
 T_jup = 3.347 
[ show covariance matrix ]

Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]

Physical Parameter Table
Parameter Symbol Value Units Sigma Reference Notes
absolute magnitude H 8.3   n/a MPO492750 IRAS observations used: 14
magnitude slope G 0.24   n/a PDS3 (MPC 17258) Fit
diameter diameter 85.877 km 3.141 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (  
rotation period rot_per 3.7474 h n/a LCDB (Rev. 2019-August); Warner et al., 2009 Published Reference List:
[Lagerkvist, C.-I.; Rickman, H.; Scaltriti, F.; Zappala, V. (1981) Astron. Astrophys. 104, 148-149.]
[Lagerkvist, C.-I.; Rickman, H. (1981) Moon Planets 24, 437-440.]
[Surdej, J.; Louis, R.; Cramer, N.; Rufener, F.; et al. (1983) Astron. Astrophys. Suppl. Ser. 54, 371-378.]
[Weidenschilling, S.J.; Chapman, C.R.; Davis, D.R.; Greenberg, R.; et al. (1987) Icarus 70, 191-245.]
[Drummond, J.D.; Weidenschilling, S.J.; Chapman, C.R.; Davis, D.R. (1988) Icarus 76, 19-77.]
[Magnusson, P. (1990) Icarus 85, 229-240.]
[Drummond, J.D.; Weidenschilling, S.J.; Chapman, C.R.; Davis, D.R. (1991) Icarus 89, 44-64.]
[Erikson, A.; Magnusson, P. (1993) Icarus 103, 62-66.]
[Michalowski, T. (1993) Icarus 106, 563-572.]
[De Angelis, G. (1995) Planet. Space Sci. 43, 649-682.]
[Michalowski, T. (1996) Icarus 123, 456-462.]
[Shevchenko, V.G.; Bel'skaya, I.N.; Krugly, Yu.N.; Chiorny, V.G.; Gaftonyuk, N.M. (2002) Icarus 155, 365-374.]
[Tungalag, N.; Shevchenko, V.G.; Lupishko, D.F. (2002) Kin. Fiz. Neb. Tel 18, 508-516; Kinematics and Physics of Celestial Bodies 18, ???-???.]
[Torppa, J.; Kaasalainen, M.; Michalowski, T.; Kwiatkowski, T.; et al. (2003) Icarus 164, 346-383.]
[Proyecto ECLA (Silvia Alonso Perez) (2011)]
[Alton, K.B. (2012) Minor Planet Bull. 39, 107-108.]
[Hanus, J.; Marchis, F.; Durech, J. (2013) Icarus 226, 1045-1057.]
[Behrend, R. (2015) Observatoire de Geneve web site,]
[Mizoguchi, T.; Tanaka, A.; Nakata, A.; Hirono, K.; et a. (2017) Minor Planet Bull. 44, 190.]
geometric albedo albedo 0.040   0.010 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (  
B-V BV 0.720   0.021 EAR-A-5-DDR-UBV-MEAN-VALUES-V1.2 #obs=13; phase (min.=4.34, mean=14.75, max.=24.15) deg.
U-B UB 0.233   0.017 EAR-A-5-DDR-UBV-MEAN-VALUES-V1.2 #obs=7; phase (min.=4.34, mean=11.63, max.=20.88) deg.
Tholen spectral type spec_T M   n/a EAR-A-5-DDR-TAXONOMY-V4.0 used 7 color indices; used ground-based radiometric albedo
SMASSII spectral type spec_B X   n/a EAR-A-5-DDR-TAXONOMY-V4.0 based on a high-resolution spectrum by Xu et al. (1995) or Bus and Binzel (2002)

201 Penelope (A879 PA)          Discovered 1879-Aug-07 by Palisa, J. at Pola
Reference: DISCOVERY.DBLast Updated: 2003-08-29

[ show close-approach data ]
Alternate Designations
 A879 PA = A869 GA 
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]
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