+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   2113 Ehrdni (1972 RJ2) Classification: Main-belt Asteroid          SPK-ID: 2002113 [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] [ show orbit diagram ] Orbital Elements at Epoch 2459000.5 (2020-May-31.0) TDB Reference: JPL 22 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .09648504293782793 6.7165e-08   a 2.473749570279193 1.0313e-08 au q 2.235069736773372 1.6036e-07 au i 6.430691984803909 4.5068e-06 deg node 23.35307794901399 2.8186e-05 deg peri 348.7153681244251 3.3552e-05 deg M 90.88345757282207 1.8849e-05 deg tp 2458641.731450504230 (2019-Jun-07.23145050) 7.3742e-05 TDB period 1421.124165693056 3.89 8.8872e-06 2.433e-08 d yr n .2533205814739169 1.5842e-09 deg/d Q 2.712429403785015 1.1308e-08 au   Orbit Determination Parameters    # obs. used (total)      2412      data-arc span      22754 days (62.30 yr)      first obs. used      1958-01-11      last obs. used      2020-04-29      planetary ephem.      DE431      SB-pert. ephem.      SB431-N16      condition code      0      norm. resid. RMS      .42637      source      ORB      producer      Otto Matic      solution date      2020-May-20 01:35:09   Additional Information  Earth MOID = 1.23577 au   Jupiter MOID = 2.71963 au   T_jup = 3.467  [ 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 12.7   n/a MPO502173   diameter diameter 7.043 km 2.082 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2016AJ....152...63N)   rotation period rot_per 13.2 h n/a LCDB (Rev. 2019-August); Warner et al., 2009 Result based on fragmentary lightcurve(s), may be completely wrong. Published Reference List: [Binzel, R.P. (1987) Icarus 72, 135-208.] geometric albedo albedo 0.238   0.157 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2016AJ....152...63N)   B-V BV 0.840   0.030 EAR-A-5-DDR-UBV-MEAN-VALUES-V1.2 #obs=1; phase=3.29 deg. 2113 Ehrdni           Discovered 1972 Sept. 11 by N. S. Chernykh at the Crimean Astrophysical Observatory. Named in memory of Ehrdni Tel'dzhievich Delikov (1922-1942), a hero from the Kalmyk S.S.R. who was killed in the Great Patriotic War (1941-1945). NOTE: some special characters may not display properly (any characters within {} are an attempt to place the proper accent above a character) Reference: MPC 5283 Last Updated: 2007-10-23 [ show close-approach data ] Alternate Designations  1972 RJ2 = 1958 AA = 1976 UQ2  [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] 2020-Oct-20 03:06 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin