+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   21000 L'Encyclopedie (1987 BY1) Classification: Main-belt Asteroid          SPK-ID: 2021000 [ 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 25 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .2315661806602612 3.1721e-08   a 2.558124451209248 1.1125e-08 au q 1.965749342389095 7.7511e-08 au i 12.93450188514796 5.6014e-06 deg node 136.1649186996441 3.0681e-05 deg peri 328.8173955084695 3.7099e-05 deg M 115.4526811396247 1.9893e-05 deg tp 2458721.227564256882 (2019-Aug-25.72756426) 8.2028e-05 TDB period 1494.448419598506 4.09 9.7488e-06 2.669e-08 d yr n .2408915525480074 1.5714e-09 deg/d Q 3.1504995600294 1.3701e-08 au   Orbit Determination Parameters    # obs. used (total)      1146      data-arc span      12196 days (33.39 yr)      first obs. used      1987-01-26      last obs. used      2020-06-17      planetary ephem.      DE441      SB-pert. ephem.      SB441-N16      condition code      0      norm. resid. RMS      .51965      source      ORB      producer      Otto Matic      solution date      2021-Apr-13 03:35:50   Additional Information  Earth MOID = .993181 au   Jupiter MOID = 2.0149 au   T_jup = 3.364  [ 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 15.02   n/a E2021B10   diameter diameter 5.886 km 0.275 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)   geometric albedo albedo 0.067   0.022 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)   21000 L´Encyclopédie           Discovered 1987 Jan. 26 by E. W. Elst at the European Southern Observatory. The Encyclopédie or Dictionnaire raisonné des sciences, des arts et des métiers (1751-1772), by Diderot and d´Alembert, may be considered the principal work of the Age of Enlightenment. NOTE: some special characters may not display properly (any characters within {} are an attempt to place the proper accent above a character) Reference: 20030106/MPCPages.arc Last Updated: 2003-10-02 [ show close-approach data ] Alternate Designations  1987 BY1 = 2000 JS79  [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] 2021-Apr-22 14:17 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin