+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   2 Pallas (A802 FA) Classification: Main-belt Asteroid          SPK-ID: 2000002 [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] [ show orbit diagram ] Orbital Elements at Epoch 2459200.5 (2020-Dec-17.0) TDB Reference: JPL 41 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .2297500074804646 3.1921e-08   a 2.774381672752594 4.2539e-09 au q 2.136967462684022 8.8318e-08 au i 34.85445947332398 3.4563e-06 deg node 172.965883851247 6.2665e-06 deg peri 310.2881130704992 9.1238e-06 deg M 187.5863508408548 8.915e-06 deg tp 2460008.882457283196 (2023-Mar-05.38245728) 4.2746e-05 TDB period 1687.903979999453 4.62 3.882e-06 1.063e-08 d yr n .2132822745048072 4.9053e-10 deg/d Q 3.411795882821167 5.2312e-09 au   Orbit Determination Parameters    # obs. used (total)      8875      data-arc span      78963 days (216.19 yr)      first obs. used      1804-08-27      last obs. used      2020-11-05      planetary ephem.      DE441      SB-pert. ephem.      SB441-N16      condition code      0      norm. resid. RMS      .35096      source      ORB      producer      Otto Matic      solution date      2021-Apr-12 10:09:26   Additional Information  Earth MOID = 1.23487 au   Jupiter MOID = 1.84906 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 4.21   n/a E2021B10 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. 2020-October); 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 (A802 FA)          Discovered 1802-Mar-28 by Olbers, H. W. at Bremen Reference: DISCOVERY.DB Last Updated: 2003-08-29 [ show close-approach data ] [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] 2021-Apr-16 00:31 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin