+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   5999 Plescia (1987 HA) Classification: Mars-crossing Asteroid          SPK-ID: 2005999 [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ] [ show orbit diagram ] Orbital Elements at Epoch 2459200.5 (2020-Dec-17.0) TDB Reference: JPL 26 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .3060675049221036 4.2957e-08   a 2.279685452604044 6.2946e-09 au q 1.581947814118308 9.8527e-08 au i 23.17093661494768 5.9089e-06 deg node 71.13261648644408 1.2176e-05 deg peri 71.41952536623886 1.8103e-05 deg M 307.7245714376617 1.1101e-05 deg tp 2459383.060123060551 (2021-Jun-17.56012306) 3.8955e-05 TDB period 1257.21866102782 3.44 5.2071e-06 1.426e-08 d yr n .2863463700941947 1.186e-09 deg/d Q 2.97742309108978 8.2212e-09 au   Orbit Determination Parameters    # obs. used (total)      1450      data-arc span      12325 days (33.74 yr)      first obs. used      1987-04-23      last obs. used      2021-01-19      planetary ephem.      DE431      SB-pert. ephem.      SB431-N16      condition code      0      norm. resid. RMS      .4069      source      ORB      producer      Otto Matic      solution date      2021-Feb-24 01:28:20   Additional Information  Earth MOID = .729904 au   Jupiter MOID = 2.49386 au   T_jup = 3.441  [ 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 14.5   n/a MPO435756   diameter diameter 7.078 km 1.897 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2015ApJ...814..117N)   rotation period rot_per 5.392 h n/a LCDB (Rev. 2020-October); Warner et al., 2009 Published Reference List: [Pravec, P.; Wolf, M.; Sarounova, L. (2011) http://www.asu.cas.cz/~ppravec/neo.htm] [Warner, B.D. (2018) Minor Planet Bull. 45, 380-386.] [Skiff, B.A.; McLelland, K.P.; Sanborn, J.; Pravec, P.; Koehn, B.W. (2019). Minor Planet Bull. 46, 458-503.] geometric albedo albedo 0.067   0.047 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2015ApJ...814..117N)   5999 Plescia (1987 HA)          Discovered 1987-Apr-23 by Shoemaker, C. S. at Palomar Reference: DISCOVERY.DB Last Updated: 2003-08-29 Alternate Designations  1987 HA = 1989 XQ  [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ] 2021-Feb-27 05:19 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin