+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   17831 Ussery (1998 HW35) Classification: Main-belt Asteroid          SPK-ID: 2017831 [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] [ show orbit diagram ] Orbital Elements at Epoch 2459000.5 (2020-May-31.0) TDB Reference: JPL 31 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .06305127200367684 3.309e-08   a 2.677997498155286 1.151e-08 au q 2.509146349473931 8.9576e-08 au i 2.390226155449622 4.1235e-06 deg node 129.9835756055624 0.00010164 deg peri 305.6021056196237 0.00010969 deg M 134.7130931499993 4.2277e-05 deg tp 2458401.508051680084 (2018-Oct-10.00805168) 0.0001864 TDB period 1600.713756569035 4.38 1.0319e-05 2.825e-08 d yr n .2248996727382558 1.4499e-09 deg/d Q 2.846848646836642 1.2235e-08 au   Orbit Determination Parameters    # obs. used (total)      1726      data-arc span      10502 days (28.75 yr)      first obs. used      1991-10-05      last obs. used      2020-07-06      planetary ephem.      DE431      SB-pert. ephem.      SB431-N16      condition code      0      norm. resid. RMS      .50425      source      ORB      producer      Otto Matic      solution date      2020-Nov-13 02:18:37   Additional Information  Earth MOID = 1.52521 au   Jupiter MOID = 2.30119 au   T_jup = 3.374  [ hide covariance matrix ] Orbital Elements at Epoch 2456798.5 (2014-May-21.0) TDB Reference: JPL 31 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .06221103135727883 3.3025e-08   q 2.512103530983068 8.9178e-08 au tp 2456807.204216725844 (2014-May-29.70421673) 0.00018484 TDB node 129.9931446685907 0.00010165 deg peri 307.3285712764682 0.00010989 deg i 2.389233366258741 4.1219e-06 deg   Orbit Determination Parameters    # obs. used (total)      1726      data-arc span      10502 days (28.75 yr)      first obs. used      1991-10-05      last obs. used      2020-07-06      planetary ephem.      DE431      SB-pert. ephem.      SB431-N16      condition code      0      norm. resid. RMS      .50425      source      ORB      producer      Otto Matic      solution date      2020-Nov-13 02:18:37   Additional Information  Jupiter MOID = 2.30119 au   T_jup = 3.374  Orbit Covariance (6×6)   e q tp node peri i e 1.090640981796872E-15 -2.923950616409984E-15 -4.749442602846923E-13 -1.471450255635168E-15 -1.448416405878395E-13 3.186012331910333E-16 q -2.923950616409984E-15 7.952627688560149E-15 1.893626825214077E-12 4.287474506898382E-15 5.265706278659638E-13 -8.498561591602804E-16 tp -4.749442602846923E-13 1.893626825214077E-12 3.416704895429722E-8 -2.969186503069855E-11 7.735591869065443E-9 -3.602555851398865E-12 node -1.471450255635168E-15 4.287474506898382E-15 -2.969186503069855E-11 1.033312686921048E-8 -1.033047778267835E-8 1.340670362267738E-10 peri -1.448416405878395E-13 5.265706278659638E-13 7.735591869065443E-9 -1.033047778267835E-8 1.2075414942398E-8 -1.34776588618019E-10 i 3.186012331910333E-16 -8.498561591602804E-16 -3.602555851398865E-12 1.340670362267738E-10 -1.34776588618019E-10 1.698970095433165E-11 [ 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 14.2   n/a MPO381406   diameter diameter 4.200 km 0.193 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)   geometric albedo albedo 0.251   0.027 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)   17831 Ussery           Discovered 1998 Apr. 20 by the Lincoln Laboratory Near-Earth Asteroid Research Team at Socorro. Robert Francis Ussery (b. 1985) was awarded second place in the 2003 Intel International Science and Engineering Fair for his engineering project. He attends the Seton Home Study School, Front Royal, Virginia, 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: 20040614/MPCPages.arc Last Updated: 2009-12-11 [ show close-approach data ] Alternate Designations  1998 HW35 = 1999 NP16  [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] 2021-Jan-21 03:08 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin