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2 Pallas
Classification: Main-belt Asteroid          SPK-ID: 2000002
Ephemeris | Orbit Diagram | Orbital Elements | Physical Parameters | Discovery Circumstances | Close-Approach Data ]

[ show orbit diagram ]
Orbital Elements at Epoch 2457000.5 (2014-Dec-09.0) TDB
Reference: JPL 26 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .2312736282433415 1.9294e-08  
a 2.771606108489468 2.1815e-09 AU
q 2.1306067077177 5.3551e-08 AU
i 34.84099788068097 2.135e-06 deg
node 173.0962475866183 3.7364e-06 deg
peri 309.9303277309815 5.5406e-06 deg
M 78.22870368538561 4.8807e-06 deg
tp 2456634.265439912991
2.2678e-05 JED
period 1685.371678425934
n .2136027349980301 2.5219e-10 deg/d
Q 3.412605509261236 2.686e-09 AU
  Orbit Determination Parameters
   # obs. used (total)      7829  
   data-arc span      68635 days (187.91 yr)  
   first obs. used      1825-03-23  
   last obs. used      2013-02-20  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-BIG16  
   condition code      0  
   fit RMS      .54256  
   data source      ORB  
   producer      Davide Farnocchia  
   solution date      2013-Jul-16 08:46:11  

Additional Information
 Earth MOID = 1.23071 AU 
 T_jup = 3.043 
[ show covariance matrix ]

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

Physical Parameter Table
Parameter Symbol Value Units Sigma Reference Notes
absolute magnitude H 4.13 mag n/a IRAS-A-FPA-3-RDR-IMPS-V6.0 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 Asteroid Lightcurve DataBase (Rev. 2014-Mar-01) 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 Bul. 35, 63-66.]
[Durech, J.; Kaasalainen, M.; Herald, D.; Dunham, D.; et al. (2011) Icarus 214, 652-670.]
geometric albedo albedo 0.1587   0.013 IRAS-A-FPA-3-RDR-IMPS-V6.0 IRAS observations used: 19
B-V BV .635 mag .031 EAR-A-5-DDR-UBV-MEAN-VALUES-V1.1 #obs=32; phase (min.=.19, mean=13.73, max.=25.65) deg.
U-B UB .284 mag .018 EAR-A-5-DDR-UBV-MEAN-VALUES-V1.1 #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

[ show close-approach data ]
Ephemeris | Orbit Diagram | Orbital Elements | Physical Parameters | Discovery Circumstances | Close-Approach Data ]
FirstGov 2014-Sep-02 11:40 UT
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