+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   2683 Brian (1981 AD1) Classification: Main-belt Asteroid          SPK-ID: 2002683 [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ] [ show orbit diagram ] Orbital Elements at Epoch 2459000.5 (2020-May-31.0) TDB Reference: JPL 32 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .05779017531616008 3.4916e-08   a 2.91664569079262 1.2779e-08 au q 2.748092224986592 1.0209e-07 au i 1.480660051542347 3.5517e-06 deg node 342.1741137676394 0.00015513 deg peri 18.58454089600052 0.00015911 deg M 90.05534294559958 3.5209e-05 deg tp 2458545.374757883882 (2019-Mar-02.87475788) 0.00017853 TDB period 1819.38219102422 4.98 1.1957e-05 3.274e-08 d yr n .1978693656429265 1.3004e-09 deg/d Q 3.085199156598649 1.3517e-08 au   Orbit Determination Parameters    # obs. used (total)      2953      data-arc span      33084 days (90.58 yr)      first obs. used      1929-09-29      last obs. used      2020-04-28      planetary ephem.      DE431      SB-pert. ephem.      SB431-N16      condition code      0      norm. resid. RMS      .43908      source      ORB      producer      Otto Matic      solution date      2020-May-20 01:43:44   Additional Information  Earth MOID = 1.74453 au   Jupiter MOID = 2.20226 au   T_jup = 3.278  [ 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 11.8   n/a MPO332842   diameter diameter 11.077 km 0.180 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2014ApJ...791..121M)   rotation period rot_per 22.528 h n/a LCDB (Rev. 2019-August); Warner et al., 2009 sidereal period (not synodic); Result based on less than full coverage, so that the period may be wrong by 30 percent or so. Published Reference List: [Durech, J.; Hanus, J. (2018) Astron. Astrophys. 620, A91.] geometric albedo albedo 0.209   0.045 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2012ApJ...759L...8M)   2683 Brian (1981 AD1)          Discovered 1981-Jan-10 by Thomas, N. G. at Flagstaff (AM) Discovered at the Anderson Mesa station, which is operated by the Lowell Observatory. Reference: DISCOVERY.DB Last Updated: 2003-08-29 Alternate Designations  1981 AD1 = 1929 ST = 1939 UF = 1969 UG2 = 1978 PM  [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ] 2020-Jul-04 19:04 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin