+ 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 2459396.5 (2021-Jul-01.0) TDB Reference: JPL 39 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .1463756233568443 1.5778e-08   a 2.341115433861555 6.1755e-09 au q 1.998433202879741 3.6932e-08 au i 10.01585521151402 5.8131e-07 deg node 182.1305737781555 2.6322e-06 deg peri 340.7676696422699 5.7758e-06 deg M 310.3644375792801 5.8068e-06 deg tp 2459576.894426531962 (2021-Dec-28.39442653) 2.1547e-05 TDB period 1308.376300867636 3.58 5.177e-06 1.417e-08 d yr n .2751501993434684 1.0887e-09 deg/d Q 2.683797664843369 7.0795e-09 au   Orbit Determination Parameters    # obs. used (total)      2642      data-arc span      17886 days (48.97 yr)      first obs. used      1972-04-19      last obs. used      2021-04-08      planetary ephem.      DE441      SB-pert. ephem.      SB441-N16      condition code      0      norm. resid. RMS      .43441      source      ORB      producer      Otto Matic      solution date      2021-Jul-08 13:35:42   Additional Information  Earth MOID = 1.00892 au   Jupiter MOID = 2.2953 au   T_jup = 3.529  [ 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 13.05   n/a MPCxxxxx   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-Jul-26 14:27 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin