+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   136993 (1998 ST49) Classification: Apollo [NEO]          SPK-ID: 2136993 [ 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 139 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .5952477397868717 1.5153e-08   a 2.308493344730363 2.4116e-09 au q .9343678989665786 3.4717e-08 au i 24.48193391458129 6.0185e-06 deg node 18.20475457436982 2.4011e-06 deg peri 48.10681243004606 5.7543e-06 deg M 51.21621741641049 1.6001e-06 deg tp 2458818.237901289885 (2019-Nov-30.73790129) 5.4447e-06 TDB period 1281.124589935406 3.51 2.0075e-06 5.496e-09 d yr n .2810031146292737 4.4034e-10 deg/d Q 3.682618790494147 3.8471e-09 au   Orbit Determination Parameters    # obs. used (total)      732      # delay obs. used      5      # Doppler obs. used      2      data-arc span      7882 days (21.58 yr)      first obs. used      1998-09-29      last obs. used      2020-04-28      planetary ephem.      DE431      SB-pert. ephem.      SB431-N16      condition code      0      norm. resid. RMS      .38847      source      ORB      producer      Otto Matic      solution date      2020-Jul-08 06:59:55   Additional Information  Earth MOID = .056035 au   Jupiter MOID = 2.16054 au   T_jup = 3.228  [ 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 17.77   n/a E2021B55   rotation period rot_per 2.3017 h n/a LCDB (Rev. 2020-October); Warner et al., 2009 Published Reference List: [Galad, A. (2007) Earth, Moon, and Planets 100, 77-82.] [Hicks, M.; Brewer, M.; Somers, J. (2012) Astronomer's Telegram 4588. http://www.astronomerstelegram.org] [Observers at Arecibo and Goldstone. (2012) http://www.naic.edu/~pradar/ http://www.jpl.nasa.gov/asteroidwatch] SMASSII spectral type spec_B Q   n/a Binzel et al. (2001) Icarus 151, 139-149   136993 (1998 ST49)          Discovered 1998-Sep-29 by LINEAR at Socorro Reference: 20061205/Numbers.arc Last Updated: 2006-12-13 [ show close-approach data ] [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] 2021-Mar-02 06:08 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin