+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   21791 Mattweegman (1999 SR7) Classification: Main-belt Asteroid          SPK-ID: 2021791 [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ] [ show orbit diagram ] Orbital Elements at Epoch 2459396.5 (2021-Jul-01.0) TDB Reference: JPL 28 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .1508935846384105 4.4871e-08   a 2.376970243536878 9.2971e-09 au q 2.018300682910763 1.0677e-07 au i 7.600345188177903 4.9626e-06 deg node 48.7196752942833 2.9193e-05 deg peri 289.2963662513672 3.3664e-05 deg M 343.8319215825818 1.9818e-05 deg tp 2459456.615982655145 (2021-Aug-30.11598265) 7.3853e-05 TDB period 1338.548292327491 3.66 7.8532e-06 2.15e-08 d yr n .268948085073588 1.5779e-09 deg/d Q 2.735639804162993 1.07e-08 au   Orbit Determination Parameters    # obs. used (total)      1473      data-arc span      14518 days (39.75 yr)      first obs. used      1981-09-24      last obs. used      2021-06-24      planetary ephem.      DE441      SB-pert. ephem.      SB441-N16      condition code      0      norm. resid. RMS      .50496      source      ORB      producer      Otto Matic      solution date      2021-Jul-08 05:11:32   Additional Information  Earth MOID = 1.02437 au   Jupiter MOID = 2.66592 au   T_jup = 3.514  [ 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 14.41   n/a E2021B10   diameter diameter 3.350 km 0.120 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)   geometric albedo albedo 0.286   0.040 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2012ApJ...759L...8M)   21791 Mattweegman           Discovered 1999 Sept. 29 by the Lincoln Laboratory Near-Earth Asteroid Research Team at Socorro. Matt Moraco Weegman (b. 1988) was awarded second place in the 2005 Intel International Science and Engineering Fair for his environmental sciences team project. He attends the Winona Senior High School, Winona, Minnesota, U.S.A. NOTE: some special characters may not display properly (any characters within {} are an attempt to place the proper accent above a character) Reference: 20050822/MPCPages.arc Last Updated: 2005-08-26 Alternate Designations  1999 SR7 = 1981 SV8 = 1981 UL25 = 1998 HY19  [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ] 2021-Aug-01 04:50 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin