+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   20958 (A900 MA) Classification: Mars-crossing Asteroid          SPK-ID: 2020958 [ 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 32 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .2956076466142227 3.1244e-08   a 2.328865898159973 7.4452e-09 au q 1.640435330724785 7.2552e-08 au i 8.162387817344088 3.7764e-06 deg node 97.46678979954879 2.9233e-05 deg peri 187.8582052007525 3.0249e-05 deg M 308.1894806561004 1.085e-05 deg tp 2459387.323108537478 (2021-Jun-21.82310854) 3.9669e-05 TDB period 1298.120920716294 3.55 6.225e-06 1.704e-08 d yr n .2773239335834404 1.3299e-09 deg/d Q 3.017296465595161 9.646e-09 au   Orbit Determination Parameters    # obs. used (total)      1846      data-arc span      44061 days (120.63 yr)      first obs. used      1900-06-29      last obs. used      2021-02-15      planetary ephem.      DE441      SB-pert. ephem.      SB441-N16      condition code      0      norm. resid. RMS      .49294      source      ORB      producer      Otto Matic      solution date      2021-Apr-13 03:35:15   Additional Information  Earth MOID = .622511 au   Jupiter MOID = 2.16049 au   T_jup = 3.500  [ 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 14.45   n/a E2021B10   diameter diameter 2.847 km 0.425 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2015ApJ...814..117N)   geometric albedo albedo 0.399   0.183 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2015ApJ...814..117N)   20958 (A900 MA)          Discovered 1900-Jun-29 by Keeler, J. E. at Mt. Hamilton Reference: 20010208/Numbers.arc Last Updated: 2004-04-19 Alternate Designations  A900 MA = 1999 CC53 = 2000 TO50  [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ] 2021-Apr-14 15:02 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin