+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   21779 (1999 RE231) Classification: Main-belt Asteroid          SPK-ID: 2021779 [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] [ show orbit diagram ] Orbital Elements at Epoch 2459396.5 (2021-Jul-01.0) TDB Reference: JPL 29 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .119714773256457 4.464e-08   a 2.553312692889166 1.0007e-08 au q 2.247643442807106 1.1246e-07 au i 10.44790741432634 4.7704e-06 deg node 120.223527710905 1.6936e-05 deg peri 178.9303749856797 2.2536e-05 deg M 171.9977193334837 1.3604e-05 deg tp 2458684.508808663365 (2019-Jul-20.00880866) 5.5839e-05 TDB period 1490.233881440136 4.08 8.7611e-06 2.399e-08 d yr n .2415728191954019 1.4202e-09 deg/d Q 2.858981942971226 1.1205e-08 au   Orbit Determination Parameters    # obs. used (total)      1384      data-arc span      10275 days (28.13 yr)      first obs. used      1992-12-24      last obs. used      2021-02-10      planetary ephem.      DE441      SB-pert. ephem.      SB441-N16      condition code      0      norm. resid. RMS      .50593      source      ORB      producer      Otto Matic      solution date      2021-Apr-13 03:53:16   Additional Information  Earth MOID = 1.2315 au   Jupiter MOID = 2.34852 au   T_jup = 3.406  [ 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 14.56   n/a MPCxxxxx   diameter diameter 3.115 km 0.135 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)   geometric albedo albedo 0.200   0.064 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)   21779 (1999 RE231)          Discovered 1999-Sep-08 by CSS at Catalina Reference: 20010208/Numbers.arc Last Updated: 2004-04-19 [ show close-approach data ] Alternate Designations  1999 RE231 = 1998 HU114 = 1999 VZ202  [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] 2021-Jul-31 07:15 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin