+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   249655 (1999 TW317) Classification: Main-belt Asteroid          SPK-ID: 2249655 [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] [ show orbit diagram ] Orbital Elements at Epoch 2459000.5 (2020-May-31.0) TDB Reference: JPL 12 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .06435578189412876 7.2606e-08   a 3.087455494872671 3.9114e-08 au q 2.888759882436816 2.3453e-07 au i 9.133128634698085 9.9771e-06 deg node 355.9017738154097 3.8053e-05 deg peri 50.50041271480437 8.2401e-05 deg M 256.0290476025194 7.6368e-05 deg tp 2459572.780578347513 (2021-Dec-24.28057835) 0.00042522 TDB period 1981.524680253836 5.43 3.7655e-05 1.031e-07 d yr n .1816782821770777 3.4525e-09 deg/d Q 3.286151107308526 4.1631e-08 au   Orbit Determination Parameters    # obs. used (total)      250      data-arc span      7166 days (19.62 yr)      first obs. used      1999-10-12      last obs. used      2019-05-26      planetary ephem.      DE431      SB-pert. ephem.      SB431-N16      condition code      0      norm. resid. RMS      .56287      source      ORB      producer      Otto Matic      solution date      2020-Feb-25 10:25:56   Additional Information  Earth MOID = 1.90673 au   Jupiter MOID = 1.99416 au   T_jup = 3.203  [ 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 15.5   n/a MPO437159   diameter diameter 3.283 km 0.635 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)   geometric albedo albedo 0.103   0.137 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)   249655 (1999 TW317)          Discovered 1999-Oct-12 by Spacewatch at Kitt Peak Reference: 20100923/Numbers.arc Last Updated: 2010-09-27 [ show close-approach data ] Alternate Designations  1999 TW317 = 2002 EX48  [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] 2020-Aug-03 15:41 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin