+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   15520 (1999 XK98) Classification: Main-belt Asteroid          SPK-ID: 2015520 [ 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 37 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .1283968764367042 3.4859e-08   a 2.654424766563372 1.1793e-08 au q 2.313604917800408 9.2317e-08 au i 11.69177065582486 4.1121e-06 deg node 263.029051181159 2.1161e-05 deg peri 322.411179086868 2.7805e-05 deg M 130.845527413959 1.8298e-05 deg tp 2458426.369737255026 (2018-Nov-03.86973725) 8.0009e-05 TDB period 1579.625216644132 4.32 1.0527e-05 2.882e-08 d yr n .2279021607193696 1.5188e-09 deg/d Q 2.995244615326337 1.3307e-08 au   Orbit Determination Parameters    # obs. used (total)      2081      data-arc span      14681 days (40.19 yr)      first obs. used      1980-07-12      last obs. used      2020-09-21      planetary ephem.      DE431      SB-pert. ephem.      SB431-N16      condition code      0      norm. resid. RMS      .44743      source      ORB      producer      Otto Matic      solution date      2020-Oct-22 16:40:17   Additional Information  Earth MOID = 1.31411 au   Jupiter MOID = 2.06863 au   T_jup = 3.348  [ 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 12.7   n/a MPO350926   diameter diameter 8.641 km 0.165 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2014ApJ...791..121M)   rotation period rot_per 8.7904 h n/a LCDB (Rev. 2019-August); Warner et al., 2009 Published Reference List: [Clark, M. (2016) Minor Planet Bull. 43, 132-135.] geometric albedo albedo 0.237   0.030 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2014ApJ...791..121M)   15520 (1999 XK98)          Discovered 1999-Dec-07 by LINEAR at Socorro Reference: 20000621/Numbers.arc Last Updated: 2004-04-19 [ show close-approach data ] Alternate Designations  1999 XK98 = 1990 VX11 = 1993 MM = 1998 QF90  [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] 2020-Oct-27 08:42 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin