+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   19112 (1981 EN31) Classification: Main-belt Asteroid          SPK-ID: 2019112 [ 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 29 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .1123792991109287 2.8169e-08   a 2.308034581909256 7.2012e-09 au q 2.048659273270508 6.7133e-08 au i 4.212820068422395 3.045e-06 deg node 160.0096570409035 4.5976e-05 deg peri 171.4438371818633 4.8464e-05 deg M 337.9728793853383 1.5219e-05 deg tp 2459278.864095193573 (2021-Mar-05.36409519) 5.4201e-05 TDB period 1280.74271545544 3.51 5.994e-06 1.641e-08 d yr n .2810869003240684 1.3155e-09 deg/d Q 2.567409890548003 8.0105e-09 au   Orbit Determination Parameters    # obs. used (total)      1666      data-arc span      14406 days (39.44 yr)      first obs. used      1981-02-09      last obs. used      2020-07-20      planetary ephem.      DE441      SB-pert. ephem.      SB441-N16      condition code      0      norm. resid. RMS      .51633      source      ORB      producer      Otto Matic      solution date      2021-Apr-13 02:46:03   Additional Information  Earth MOID = 1.03619 au   Jupiter MOID = 2.73463 au   T_jup = 3.574  [ 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 15.43   n/a E2021B10   diameter diameter 4.462 km 0.074 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)   geometric albedo albedo 0.080   0.006 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)   19112 (1981 EN31)          Discovered 1981-Mar-02 by Bus, S. J. at Siding Spring Reference: 20001211/Numbers.arc Last Updated: 2004-04-19 [ show close-approach data ] Alternate Designations  1981 EN31 = 1999 LQ11  [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] 2021-Apr-19 01:30 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin