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2 Pallas
Classification: Main-belt Asteroid          SPK-ID: 2000002
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 36 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .229972273669372 3.1683e-08  
a 2.773841433753834 3.9896e-09 au
q 2.135934812435154 8.759e-08 au
i 34.83293223299784 3.4627e-06 deg
node 173.0247414629276 6.2377e-06 deg
peri 310.2023915653847 9.1084e-06 deg
M 144.9756780217629 8.7765e-06 deg
tp 2458320.962354266460
(2018-Jul-21.46235427)
4.0424e-05 TDB
period 1687.410990603206
4.62
3.6405e-06
9.967e-09
d
yr
n .21334458647286 4.6028e-10 deg/d
Q 3.411748055072514 4.9071e-09 au
  Orbit Determination Parameters
   # obs. used (total)      8512  
   data-arc span      72427 days (198.29 yr)  
   first obs. used      1821-05-09  
   last obs. used      2019-08-26  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-N16  
   condition code      0  
   norm. resid. RMS      .36724  
   source      ORB  
   producer      Otto Matic  
   solution date      2020-Feb-22 15:13:40  

Additional Information
 Earth MOID = 1.23429 au 
 Jupiter MOID = 1.85093 au 
 T_jup = 3.042 
[ 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 4.2   n/a MPO492748 IRAS observations used: 19
magnitude slope G 0.11   n/a PDS3 (MPC 17257) Fit
diameter diameter 545 km 18 see ref. for extent computed from extent=582x556x500 km
extent extent 582x556x500 km 18 Schmidt et al. 2008, LPSC XXXIX  
GM GM 14.3 km^3/s^2 n/a JPL IOM 312.F01-006  
rotation period rot_per 7.8132 h n/a LCDB (Rev. 2019-August); Warner et al., 2009 Published Reference List:
[Schroll, A.; Haupt, H.F.; Maitzen, H.M. (1976) Icarus 27, 147-156.]
[Chang, Y.C.; Zhou, X.-h.; Yang, X.-y.; Zhang, Y.-y.; et al. (1981) Acta Astron. Sin. 22, 169-173; Chin. Astron. Astrophys. 5, 434-437.]
[Magnusson, P. (1986) Icarus 68, 1-39.]
[Lagerkvist, C.I.; Magnusson, P.; Williams, I.P.; Buontempo, M.E.; et al. (1988) Astron. Astrophys. Suppl. Ser. 73, 395-405.]
[Torppa, J.; Kaasalainen, M.; Michalowski, T.; Kwiatkowski, T.; et al. (2003) Icarus 164, 346-383.]
[Higley, S.; Hardersen, P.; Dyvig, R. (2008) Minor Planet Bull. 35, 63-66.]
[Carry, B.; Dumas, C.; Kaasalainen, M.; Berthier, J.; et al. (2010) Icarus 205, 460-472.]
[Durech, J.; Kaasalainen, M.; Herald, D.; Dunham, D.; et al. (2011) Icarus 214, 652-670.]
[Hanus, J.; Viikinkoski, M.; Marchis, F.; Durech, J.; et al (2017) Astron. Astrophys. 601, A114.]
geometric albedo albedo 0.101   0.008 EAR_A_COMPIL_5_NEOWISEDIAM_V1_0[mainbelt] (http://adsabs.harvard.edu/abs/2014ApJ...791..121M)  
B-V BV 0.635   0.031 EAR-A-5-DDR-UBV-MEAN-VALUES-V1.2 #obs=32; phase (min.=.19, mean=13.73, max.=25.65) deg.
U-B UB 0.284   0.018 EAR-A-5-DDR-UBV-MEAN-VALUES-V1.2 #obs=14; phase (min.=7.23, mean=14.81, max.=25.65) deg.
Tholen spectral type spec_T B   n/a EAR-A-5-DDR-TAXONOMY-V4.0 used 7 color indices; used ground-based radiometric albedo
SMASSII spectral type spec_B B   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)

2 Pallas          Discovered 1802-Mar-28 by Olbers, H. W. at Bremen
Reference: DISCOVERY.DBLast Updated: 2003-08-29

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