+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   21078 (1991 RR16) Classification: Outer Main-belt Asteroid          SPK-ID: 2021078 [ 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 25 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .08875237441806456 4.5299e-08   a 3.394719110868566 2.7342e-08 au q 3.0934297292966 1.6018e-07 au i 8.077977106487499 6.3346e-06 deg node 23.47018278167537 3.2658e-05 deg peri 282.700021011566 5.1759e-05 deg M 317.4500525814523 4.3713e-05 deg tp 2459666.522977452202 (2022-Mar-28.02297745) 0.00027868 TDB period 2284.568554846654 6.25 2.7601e-05 7.557e-08 d yr n .1575789876107106 1.9038e-09 deg/d Q 3.696008492440531 2.9769e-08 au   Orbit Determination Parameters    # obs. used (total)      1617      data-arc span      13029 days (35.67 yr)      first obs. used      1985-10-18      last obs. used      2021-06-20      planetary ephem.      DE441      SB-pert. ephem.      SB441-N16      condition code      0      norm. resid. RMS      .46641      source      ORB      producer      Otto Matic      solution date      2021-Jul-08 05:05:10   Additional Information  Earth MOID = 2.09221 au   Jupiter MOID = 1.58694 au   T_jup = 3.126  [ 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 12.68   n/a E2021B10   diameter diameter 14.807 km 0.167 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)   geometric albedo albedo 0.067   0.008 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)   21078 (1991 RR16)          Discovered 1991-Sep-15 by Holt, H. E. at Palomar Reference: 20010208/Numbers.arc Last Updated: 2004-04-19 [ show close-approach data ] Alternate Designations  1991 RR16 = 1985 UC6 = 1998 WF20  [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] 2021-Jul-27 03:58 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin