+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   5541 Seimei (1976 UH16) Classification: Main-belt Asteroid          SPK-ID: 2005541 [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] [ 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 .1432802521666203 3.5637e-08   a 3.187395807114929 1.9333e-08 au q 2.730704932116674 1.1385e-07 au i 12.88302433367501 4.0261e-06 deg node 193.0600069507446 1.6211e-05 deg peri 199.0823645354679 2.07e-05 deg M 319.8418410738444 1.5047e-05 deg tp 2459628.358870424451 (2022-Feb-17.85887042) 8.7946e-05 TDB period 2078.511455325654 5.69 1.891e-05 5.177e-08 d yr n .173200873672162 1.5758e-09 deg/d Q 3.644086682113184 2.2103e-08 au   Orbit Determination Parameters    # obs. used (total)      2193      data-arc span      24785 days (67.86 yr)      first obs. used      1953-08-16      last obs. used      2021-06-25      planetary ephem.      DE441      SB-pert. ephem.      SB441-N16      condition code      0      norm. resid. RMS      .44809      source      ORB      producer      Otto Matic      solution date      2021-Jul-07 23:58:47   Additional Information  Earth MOID = 1.73839 au   Jupiter MOID = 1.81971 au   T_jup = 3.143  [ 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 12.37   n/a E2021B10   diameter diameter 13.250 km 0.233 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2014ApJ...791..121M)   rotation period rot_per 25.820 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: [Waszczak, A.; Chang, C.-K.; Ofeck, E.O.; Laher, F.; et al. (2015) Astron. J. 150, A75.] geometric albedo albedo 0.145   0.028 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2014ApJ...791..121M)   5541 Seimei (1976 UH16)          Discovered 1976-Oct-22 by Kosai and Hurukawa at Kiso Reference: DISCOVERY.DB Last Updated: 2003-08-29 [ show close-approach data ] Alternate Designations  1976 UH16 = 1976 ST5 = 1987 SJ11  [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] 2021-Jul-24 15:59 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin