+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   102473 (1999 TW244) Classification: Main-belt Asteroid          SPK-ID: 2102473 [ 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 21 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .3037543810080386 3.7925e-08   a 2.671906476597491 1.5831e-08 au q 1.860303178687251 9.9839e-08 au i 12.45447749797579 3.9853e-06 deg node 189.4890428742744 2.0395e-05 deg peri 271.0067622272546 2.1171e-05 deg M 250.6109224168779 6.831e-06 deg tp 2459685.232082942113 (2022-Apr-15.73208294) 3.2248e-05 TDB period 1595.255702988807 4.37 1.4178e-05 3.882e-08 d yr n .2256691509239042 2.0056e-09 deg/d Q 3.483509774507731 2.064e-08 au   Orbit Determination Parameters    # obs. used (total)      666      data-arc span      7602 days (20.81 yr)      first obs. used      1999-09-30      last obs. used      2020-07-23      planetary ephem.      DE431      SB-pert. ephem.      SB431-N16      condition code      0      norm. resid. RMS      .53402      source      ORB      producer      Otto Matic      solution date      2020-Nov-12 19:54:34   Additional Information  Earth MOID = .924753 au   Jupiter MOID = 1.92839 au   T_jup = 3.281  [ 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 15.61   n/a E2021B55   diameter diameter 4.195 km 0.235 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)   geometric albedo albedo 0.069   0.019 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)   102473 (1999 TW244)          Discovered 1999-Oct-07 by CSS at Catalina Reference: 20051019/Numbers.arc Last Updated: 2005-10-26 [ show close-approach data ] Alternate Designations  1999 TW244 = 2001 HW  [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] 2021-Apr-11 15:14 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin