+ View the NASA Portal + Near-Earth Object (NEO) Program Search JPL JPL Small-Body Database Browser Search: [ help ]   142 Polana Classification: Main-belt Asteroid          SPK-ID: 2000142 [ Ephemeris | Orbit Diagram | Orbital Elements | Physical Parameters | Discovery Circumstances ] [ show orbit diagram ] Orbital Elements at Epoch 2456400.5 (2013-Apr-18.0) TDB Reference: MPO253360 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e 0.1356596 n/a   a 2.4184174 n/a AU q 2.0903359 n/a AU i 2.23774 n/a deg node 291.30048 n/a deg peri 291.65379 n/a deg M 186.94651 n/a deg tp 2457060.8484746 (2015-Feb-07.34847460) n/a JED period 1373.7108153 3.76 n/a n/a d yr n 0.26206389 n/a deg/d Q 2.7464989 n/a AU   Orbit Determination Parameters    # obs. used (total)      1572      first obs. used      1898-??-??      last obs. used      2013-02-06      # oppositions      44      planetary ephem.      DE403      condition code      0      fit RMS      0.55      data source      MPC:mpn      producer      MPCLINUX   Additional Information  T_jup = 3.501  [ Ephemeris | Orbit Diagram | Orbital Elements | Physical Parameters | Discovery Circumstances ] Physical Parameter Table Parameter Symbol Value Units Sigma Reference Notes absolute magnitude H 10.27 mag n/a IRAS-A-FPA-3-RDR-IMPS-V6.0 IRAS observations used: 6 diameter diameter 55.29 km 1.6 IRAS-A-FPA-3-RDR-IMPS-V6.0 IRAS observations used: 6 rotation period rot_per 9.764 h n/a Asteroid Lightcurve DataBase (Rev. 2013-May-01) Published Reference List: [Dotto, E.; Rotundi, A.; De Sanctis, M.C. (1992) in Physical Properties of Small Solar System Bodies. A. Brahic, J.-C. Gerard, J. Surdej, eds. Universite de Liege, Institut d'Astrophysique, Liege, p. 211.] [Barucci, M.A.; Di Martino, M.; Dotto, E.; Fulchignoni, M.; et al. (1994) Icarus 109, 267-273.] geometric albedo albedo 0.0451   0.003 IRAS-A-FPA-3-RDR-IMPS-V6.0 IRAS observations used: 6 B-V BV .621 mag .022 EAR-A-5-DDR-UBV-MEAN-VALUES-V1.1 #obs=7; phase (min.=1.32, mean=10.93, max.=25.85) deg. U-B UB .236 mag .035 EAR-A-5-DDR-UBV-MEAN-VALUES-V1.1 #obs=7; phase (min.=1.32, mean=10.93, max.=25.85) deg. Tholen spectral type spec_T F   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) 142 Polana          Discovered 1875-Jan-28 by Palisa, J. at Pola Reference: DISCOVERY.DB Last Updated: 2003-08-29 Alternate Designations  1954 BH = 1956 XZ = 1963 SA = A923 WA  [ Ephemeris | Orbit Diagram | Orbital Elements | Physical Parameters | Discovery Circumstances ] 2013-May-19 07:50 UT (server date/time)   Site Manager:   Donald K. Yeomans Webmaster:   Alan B. Chamberlin