+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   2328 Robeson (1972 HW) Classification: Main-belt Asteroid          SPK-ID: 2002328 [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ] [ show orbit diagram ] Orbital Elements at Epoch 2459200.5 (2020-Dec-17.0) TDB Reference: JPL 36 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .1463666595260412 3.2396e-08   a 2.340723486690047 6.7999e-09 au q 1.998119609069077 7.6939e-08 au i 10.01616970681471 3.9115e-06 deg node 182.1348646360181 1.9556e-05 deg peri 340.8277808886913 2.3515e-05 deg M 256.3637769867123 1.4508e-05 deg tp 2459577.058688101385 (2021-Dec-28.55868810) 5.3497e-05 TDB period 1308.047744070312 3.58 5.6999e-06 1.561e-08 d yr n .2752193118576631 1.1993e-09 deg/d Q 2.683327364311018 7.7951e-09 au   Orbit Determination Parameters    # obs. used (total)      2537      data-arc span      17806 days (48.75 yr)      first obs. used      1972-04-19      last obs. used      2021-01-18      planetary ephem.      DE431      SB-pert. ephem.      SB431-N16      condition code      0      norm. resid. RMS      .433      source      ORB      producer      Otto Matic      solution date      2021-Feb-24 01:02:08   Additional Information  Earth MOID = 1.00747 au   Jupiter MOID = 2.2964 au   T_jup = 3.530  [ show covariance matrix ] [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ] Physical Parameter Table Parameter Symbol Value Units Sigma Reference Notes absolute magnitude H 13.04   n/a E2021B10   diameter diameter 12.895 km 2.594 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2015ApJ...814..117N)   rotation period rot_per 18.632 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: [Higgins, D.; Oey, J. (2007) Minor Planet Bull. 34, 79-80.] geometric albedo albedo 0.074   0.034 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2015ApJ...814..117N)   SMASSII spectral type spec_B C   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) 2328 Robeson (1972 HW)          Discovered 1972-Apr-19 by Smirnova, T. at Nauchnyj Reference: DISCOVERY.DB Last Updated: 2003-08-29 [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ] 2021-Feb-27 19:44 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin