+ 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 ] [ show orbit diagram ] Orbital Elements at Epoch 2459396.5 (2021-Jul-01.0) TDB Reference: JPL 46 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .1280441288855586 2.2867e-08   a 2.655215061817321 1.0384e-08 au q 2.315230362223108 6.0978e-08 au i 11.6903276314737 1.0317e-06 deg node 263.0339404070986 3.782e-06 deg peri 322.3522811854642 1.0871e-05 deg M 221.147291157113 8.3383e-06 deg tp 2460006.036668826961 (2023-Mar-02.53666883) 3.8768e-05 TDB period 1580.330715953092 4.33 9.2707e-06 2.538e-08 d yr n .2278004194728856 1.3363e-09 deg/d Q 2.995199761411535 1.1714e-08 au   Orbit Determination Parameters    # obs. used (total)      2520      data-arc span      14861 days (40.69 yr)      first obs. used      1980-07-12      last obs. used      2021-03-20      planetary ephem.      DE441      SB-pert. ephem.      SB441-N16      condition code      0      norm. resid. RMS      .43788      source      ORB      producer      Otto Matic      solution date      2021-Jul-08 17:28:00   Additional Information  Earth MOID = 1.31618 au   Jupiter MOID = 2.06645 au   T_jup = 3.347  [ show covariance matrix ] [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ] Physical Parameter Table Parameter Symbol Value Units Sigma Reference Notes absolute magnitude H 12.77   n/a E2021B10   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. 2020-October); 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 Alternate Designations  1999 XK98 = 1990 VX11 = 1993 MM = 1998 QF90  [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ] 2021-Jul-31 11:04 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin