+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   19156 Heco (1990 SE4) Classification: Main-belt Asteroid          SPK-ID: 2019156 [ 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 28 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .005686104324721091 2.528e-08   a 2.703091396729035 1.0815e-08 au q 2.687721337047977 6.6363e-08 au i 1.243094245355253 1.2105e-06 deg node 213.215967692485 3.8541e-05 deg peri 285.2467433657526 0.00015591 deg M 163.1417178634087 0.00015049 deg tp 2458464.882499601618 (2018-Dec-12.38249960) 0.00067717 TDB period 1623.265364688274 4.44 9.742e-06 2.667e-08 d yr n .2217751994413637 1.331e-09 deg/d Q 2.718461456410092 1.0877e-08 au   Orbit Determination Parameters    # obs. used (total)      2259      data-arc span      10953 days (29.99 yr)      first obs. used      1990-09-20      last obs. used      2020-09-15      planetary ephem.      DE431      SB-pert. ephem.      SB431-N16      condition code      0      norm. resid. RMS      .47465      source      ORB      producer      Otto Matic      solution date      2021-Mar-17 02:09:59   Additional Information  Earth MOID = 1.69206 au   Jupiter MOID = 2.24423 au   T_jup = 3.366  [ 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 13.5   n/a MPO384918   diameter diameter 5.797 km 0.233 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)   geometric albedo albedo 0.145   0.015 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)   19156 Heco           Discovered 1990 Sept. 20 by T. Seki at Geisei. Joseph Heco (Hikozo Hamada, 1837--1897) was born in Harima town, Hyogo prefecture. He survived a shipwreck in 1851, was taken to the US and became one of the first Japanese to become a US citizen. Returning to Japan, he published the first Japanese newspaper, while Japan was still closed to the outside world. NOTE: some special characters may not display properly (any characters within {} are an attempt to place the proper accent above a character) Reference: 20121228/MPCPages.arc Last Updated: 2013-01-02 [ hide close-approach data ] Close-Approach Data   ...sorted by Date/Time (TDB) Date/Time (TDB) Time Uncertainty (days_HH:MM) Body Nominal Distance (au) Minimum Distance (au) Maximum Distance (au) V-relative (km/s) V-infinity (km/s) JD (TDB) Time Uncertainty (minutes) Semi-major axis (km) Semi-minor axis (km) range-LOV angle (deg) N-sigma BP Orbit Ref. Reference Modified 1976-Feb-25 12:50 00:01 Iris 0.0125033946220326 0.0125011889788575 0.0125056013059602 3.90406449589377 3.90406437812555 2442834.034484218 1.27016606732148 225.377523624512 44.6482902732031 -62.9445114264365 37476.2099200445 T 28 CATAB v2.0f-lin.ifort 2021-Mar-17 02:10:36 2021-Mar-17 02:10 Alternate Designations  1990 SE4 = 1999 TK1  [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] 2021-Apr-10 23:44 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin