+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   1796 Riga (1966 KB) Classification: Outer Main-belt Asteroid          SPK-ID: 2001796 [ 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 41 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .05628748096409302 3.3176e-08   a 3.356606094918154 1.6373e-08 au q 3.16767119324649 1.1548e-07 au i 22.58173989951353 3.7575e-06 deg node 186.7024631650922 9.7456e-06 deg peri 26.29234988083078 3.7005e-05 deg M 301.6151569826755 3.6697e-05 deg tp 2459364.789464373060 (2021-May-30.28946437) 0.00022925 TDB period 2246.202959480204 6.15 1.6435e-05 4.5e-08 d yr n .1602704682052898 1.1727e-09 deg/d Q 3.545540996589818 1.7295e-08 au   Orbit Determination Parameters    # obs. used (total)      3004      data-arc span      25602 days (70.09 yr)      first obs. used      1950-10-13      last obs. used      2020-11-16      planetary ephem.      DE431      SB-pert. ephem.      SB431-N16      condition code      0      norm. resid. RMS      .40866      source      ORB      producer      Otto Matic      solution date      2020-Dec-17 19:40:33   Additional Information  Earth MOID = 2.17587 au   Jupiter MOID = 1.42411 au   T_jup = 3.031  [ 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 9.9   n/a MPO502170 IRAS observations used: 12 diameter diameter 68.167 km 0.298 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2014ApJ...791..121M)   rotation period rot_per 22.226 h n/a LCDB (Rev. 2020-October); Warner et al., 2009 Result based on less than full coverage, so that the period may be wrong by 30 percent or so. Published Reference List: [Oey, J. (2016) Minor Planet Bull. 43, 45-51.] geometric albedo albedo 0.044   0.005 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2014ApJ...791..121M)   B-V BV 0.676   0.027 EAR-A-5-DDR-UBV-MEAN-VALUES-V1.2 #obs=1; phase=21.31 deg. U-B UB 0.289   0.040 EAR-A-5-DDR-UBV-MEAN-VALUES-V1.2 #obs=1; phase=21.31 deg. Tholen spectral type spec_T XFCU   n/a EAR-A-5-DDR-TAXONOMY-V4.0 used 7 color indices SMASSII spectral type spec_B Cb   n/a EAR-A-5-DDR-TAXONOMY-V4.0 based on a high-resolution spectrum by Xu et al. (1995) or Bus and Binzel (2002) 1796 Riga (1966 KB)          Discovered 1966-May-16 by Chernykh, N. at Nauchnyj Reference: DISCOVERY.DB Last Updated: 2003-08-29 [ show close-approach data ] Alternate Designations  1966 KB = 1935 GE = 1941 FC1 = 1947 GA = 1950 TF2 = 1953 GW = 1960 JA = A907 TG = A907 UD  [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] 2021-Jan-21 06:34 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin