+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   21189 (1994 JB) Classification: Main-belt Asteroid          SPK-ID: 2021189 [ 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 24 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .1931918904968118 4.7574e-08   a 2.54418107287815 9.4264e-09 au q 2.052665921642613 1.2218e-07 au i 3.154452989553678 3.4443e-06 deg node 65.8484596285392 0.00014065 deg peri 223.0793288980666 0.00014192 deg M 144.3278765008553 1.945e-05 deg tp 2458606.251390601276 (2019-May-02.75139060) 8.0661e-05 TDB period 1482.246566430103 4.06 8.2377e-06 2.255e-08 d yr n .2428745717165244 1.3498e-09 deg/d Q 3.035696224113686 1.1247e-08 au   Orbit Determination Parameters    # obs. used (total)      1020      data-arc span      10666 days (29.20 yr)      first obs. used      1991-11-01      last obs. used      2021-01-13      planetary ephem.      DE431      SB-pert. ephem.      SB431-N16      condition code      0      norm. resid. RMS      .52367      source      ORB      producer      Otto Matic      solution date      2021-Feb-24 02:51:17   Additional Information  Earth MOID = 1.03579 au   Jupiter MOID = 2.14165 au   T_jup = 3.415  [ 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 15.1   n/a MPO299114   diameter diameter 2.701 km 0.271 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)   geometric albedo albedo 0.242   0.091 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)   21189 (1994 JB)          Discovered 1994-May-03 by Vagnozzi, A. at Stroncone Reference: 20010208/Numbers.arc Last Updated: 2004-04-19 [ show close-approach data ] Alternate Designations  1994 JB = 1998 HH40  [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] 2021-Apr-10 19:35 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin