+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   20561 (1999 RE120) Classification: Main-belt Asteroid          SPK-ID: 2020561 [ 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 34 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .02901358041695063 3.639e-08   a 2.179175419264804 6.8388e-09 au q 2.115949737995322 8.1045e-08 au i .9516778970003494 3.1611e-06 deg node 269.9835634059399 0.00021152 deg peri 247.1282705036869 0.00021742 deg M 35.25485673523819 5.0506e-05 deg tp 2459085.432370181588 (2020-Aug-23.93237018) 0.00016479 TDB period 1174.996881868578 3.22 5.5312e-06 1.514e-08 d yr n .3063837917829176 1.4423e-09 deg/d Q 2.242401100534286 7.0372e-09 au   Orbit Determination Parameters    # obs. used (total)      1674      data-arc span      11061 days (30.28 yr)      first obs. used      1990-11-23      last obs. used      2021-03-06      planetary ephem.      DE441      SB-pert. ephem.      SB441-N16      condition code      0      norm. resid. RMS      .49787      source      ORB      producer      Otto Matic      solution date      2021-Apr-13 03:23:52   Additional Information  Earth MOID = 1.1238 au   Jupiter MOID = 2.72418 au   T_jup = 3.681  [ 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 14.82   n/a E2021B10   rotation period rot_per 4.550 h n/a LCDB (Rev. 2020-October); Warner et al., 2009 Published Reference List: [Clark, M. (2014) Minor Planet Bull. 41, 178-183.] [Chang, C.K.; Ip, W.-H.; Lin, H.-W.; Cheng, Y.C.; et al. (2015) Astrophys. J. Supp. Ser. 219, A27.] [Waszczak, A.; Chang, C.-K.; Ofeck, E.O.; Laher, F.; et al. (2015) Astron. J. 150, A75.] 20561 (1999 RE120)          Discovered 1999-Sep-09 by LINEAR at Socorro Reference: 20010109/Numbers.arc Last Updated: 2004-04-19 [ show close-approach data ] Alternate Designations  1999 RE120 = 1990 WL15 = 1998 FV19  [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] 2021-Apr-21 15:51 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin