+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   979 Ilsewa (A922 MA) Classification: Main-belt Asteroid          SPK-ID: 2000979 [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] [ show orbit diagram ] Orbital Elements at Epoch 2459200.5 (2020-Dec-17.0) TDB Reference: JPL 43 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .1380457789245514 3.8066e-08   a 3.15833915253616 1.3691e-08 au q 2.722343764116398 1.201e-07 au i 10.10988522184711 3.813e-06 deg node 230.6041826530355 2.2964e-05 deg peri 115.4452559475683 2.6258e-05 deg M 158.545558741825 1.3528e-05 deg tp 2458297.603118308952 (2018-Jun-28.10311831) 7.5888e-05 TDB period 2050.154416107459 5.61 1.3331e-05 3.65e-08 d yr n .175596529301201 1.1418e-09 deg/d Q 3.594334540955921 1.5581e-08 au   Orbit Determination Parameters    # obs. used (total)      2949      data-arc span      36004 days (98.57 yr)      first obs. used      1922-06-29      last obs. used      2021-01-24      planetary ephem.      DE431      SB-pert. ephem.      SB431-N16      condition code      0      norm. resid. RMS      .41005      source      ORB      producer      Otto Matic      solution date      2021-Feb-24 00:51:27   Additional Information  Earth MOID = 1.734 au   Jupiter MOID = 1.97294 au   T_jup = 3.167  [ hide covariance matrix ] Orbital Elements at Epoch 2456402.5 (2013-Apr-20.0) TDB Reference: JPL 43 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .1340002701646784 3.7317e-08   q 2.734393713647278 1.1669e-07 au tp 2456229.453513311290 (2012-Oct-28.95351331) 7.8427e-05 TDB node 231.2832822069764 2.2987e-05 deg peri 112.2539088032148 2.6669e-05 deg i 10.1032779785718 3.8074e-06 deg   Orbit Determination Parameters    # obs. used (total)      2949      data-arc span      36004 days (98.57 yr)      first obs. used      1922-06-29      last obs. used      2021-01-24      planetary ephem.      DE431      SB-pert. ephem.      SB431-N16      condition code      0      norm. resid. RMS      .41005      source      ORB      producer      Otto Matic      solution date      2021-Feb-24 00:51:27   Additional Information  Jupiter MOID = 1.97294 au   T_jup = 3.167  Orbit Covariance (6×6)   e q tp node peri i e 1.392577783023111E-15 -4.332475898763447E-15 2.809640936677059E-13 -3.939794581330056E-16 3.453207116880415E-14 7.549390283008143E-16 q -4.332475898763447E-15 1.361574435771013E-14 -8.041533353748935E-13 3.24242725359168E-16 -9.486151006654511E-14 -1.580419645270334E-15 tp 2.809640936677059E-13 -8.041533353748935E-13 6.150763929671609E-9 -1.078706321130737E-11 1.089941529825214E-9 2.013997419503771E-12 node -3.939794581330056E-16 3.24242725359168E-16 -1.078706321130737E-11 5.283900262875266E-10 -5.211585016002745E-10 -1.166615512705618E-11 peri 3.453207116880415E-14 -9.486151006654511E-14 1.089941529825214E-9 -5.211585016002745E-10 7.112199007284707E-10 1.17227792733946E-11 i 7.549390283008143E-16 -1.580419645270334E-15 2.013997419503771E-12 -1.166615512705618E-11 1.17227792733946E-11 1.449631266564458E-11 [ 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 9.77   n/a E2021B10   diameter diameter 35.741 km 0.602 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2014ApJ...791..121M)   rotation period rot_per 42.61 h n/a LCDB (Rev. 2020-October); Warner et al., 2009 Published Reference List: [Ferrero, A. (2013) Minor Planet Bull. 40, 31-32.] [Stephens, R.D. (2013) Minor Planet Bull. 40, 34-35.] [Durech, J.; Hanus, J.; Oszkiewsicz, D.; Vanco, R. (2016) Astron. Astrophys. 587, A48.] geometric albedo albedo 0.166   0.047 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2014ApJ...791..121M)   979 Ilsewa (A922 MA)          Discovered 1922-Jun-29 by Reinmuth, K. at Heidelberg Reference: DISCOVERY.DB Last Updated: 2003-08-29 [ show close-approach data ] Alternate Designations  A922 MA = 1932 EG1 = 1951 TW = 1966 HO = A916 KD = A923 XB  [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] 2021-Mar-06 23:32 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin