+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   18373 (1991 RQ16) Classification: Main-belt Asteroid          SPK-ID: 2018373 [ 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 30 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .1561855391117161 4.5746e-08   a 2.680512995594359 1.4161e-08 au q 2.261855628281493 1.2565e-07 au i 4.091668924301693 4.0487e-06 deg node 71.87349206435405 7.1936e-05 deg peri 260.4968460729519 7.3056e-05 deg M 256.6173942709945 1.5253e-05 deg tp 2459660.831056694232 (2022-Mar-22.33105669) 6.9412e-05 TDB period 1602.969660527996 4.39 1.2703e-05 3.478e-08 d yr n .2245831651495019 1.7797e-09 deg/d Q 3.099170362907224 1.6373e-08 au   Orbit Determination Parameters    # obs. used (total)      1255      data-arc span      10475 days (28.68 yr)      first obs. used      1991-09-15      last obs. used      2020-05-20      planetary ephem.      DE441      SB-pert. ephem.      SB441-N16      condition code      0      norm. resid. RMS      .50359      source      ORB      producer      Otto Matic      solution date      2021-Apr-13 02:27:47   Additional Information  Earth MOID = 1.25393 au   Jupiter MOID = 2.26159 au   T_jup = 3.355  [ 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 14.77   n/a E2021B10   diameter diameter 3.088 km 0.666 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)   geometric albedo albedo 0.322   0.123 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)   18373 (1991 RQ16)          Discovered 1991-Sep-15 by Holt, H. E. at Palomar Reference: 20001111/Numbers.arc Last Updated: 2004-04-19 [ show close-approach data ] Alternate Designations  1991 RQ16 = 1996 XN13  [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] 2021-Apr-19 10:19 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin