+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   1909 Alekhin (1972 RW2) Classification: Main-belt Asteroid          SPK-ID: 2001909 [ 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 38 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .2254477002123 2.9083e-08   a 2.422803625255509 6.8276e-09 au q 1.876588119875631 7.2505e-08 au i 1.795574312070955 3.1219e-06 deg node 227.4414098322967 0.00010705 deg peri 5.811852372789891 0.00010732 deg M 314.9945792332098 9.1738e-06 deg tp 2459172.701953834317 (2020-Nov-19.20195383) 3.5393e-05 TDB period 1377.449701039098 3.77 5.8226e-06 1.594e-08 d yr n .2613525559070716 1.1048e-09 deg/d Q 2.969019130635387 8.3669e-09 au   Orbit Determination Parameters    # obs. used (total)      3329      data-arc span      34413 days (94.22 yr)      first obs. used      1926-04-14      last obs. used      2020-07-02      planetary ephem.      DE431      SB-pert. ephem.      SB431-N16      condition code      0      norm. resid. RMS      .45144      source      ORB      producer      Otto Matic      solution date      2020-Nov-13 04:14:19   Additional Information  Earth MOID = .865593 au   Jupiter MOID = 2.03075 au   T_jup = 3.477  [ 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 12.8   n/a MPO358645   diameter diameter 18.681 km 0.043 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2014ApJ...791..121M)   rotation period rot_per 148.6 h n/a LCDB (Rev. 2019-August); Warner et al., 2009 Published Reference List: [Dymock, R. (2009) Minor Planet Bull. 36, 182-183.] [Waszczak, A.; Chang, C.-K.; Ofeck, E.O.; Laher, F.; et al. (2015) Astron. J. 150, A75.] geometric albedo albedo 0.060   0.004 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2014ApJ...791..121M)   1909 Alekhin (1972 RW2)          Discovered 1972-Sep-04 by Zhuravleva, L. at Nauchnyj Reference: DISCOVERY.DB Last Updated: 2003-08-29 [ show close-approach data ] Alternate Designations  1972 RW2 = 1926 GU = 1930 KF = 1930 KM = 1934 NZ = 1934 OC = 1941 FJ = 1960 FD = 1969 UU = 1971 DL  [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] 2020-Dec-06 02:57 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin