+ View the NASA Portal + Near-Earth Object (NEO) Program Search JPL JPL Small-Body Database Browser Search: [ help ]   78P/Gehrels 2 Classification: Jupiter-family Comet          SPK-ID: 1000030 [ Ephemeris | Orbit Diagram | Orbital Elements | Physical Parameters | Discovery Circumstances | Close-Approach Data ] [ show orbit diagram ] alternate orbits: [epoch=2013-03-13.0] K114/6 (default) [epoch=2006-03-09.0] K043/41 [epoch=1989-11-10.0] J974/3 [epoch=1981-11-12.0] SAO/1981 [epoch=1973-11-14.0] SAO/1973 Orbital Elements at Epoch 2456364.5 (2013-Mar-13.0) TDB Reference: JPL K114/6 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .4623087433270055 9.6757e-08   a 3.735418990461866 9.2018e-08 AU q 2.008502131181609 3.9469e-07 AU i 6.255121569087698 1.0983e-05 deg node 210.5547915095289 2.5121e-05 deg peri 192.7396504535754 4.1566e-05 deg M 58.05999968979462 1.351e-05 deg tp 2455939.213165261387 (2012-Jan-12.71316526) 8.9418e-05 JED period 2636.983488183037 7.22 9.7439e-05 2.668e-07 d yr n .136519626161198 5.0445e-09 deg/d Q 5.462335849742121 1.3456e-07 AU Additional Model Parameters  Parameter Value Uncertainty (1-sigma)  A1 [EST] 8.140741260497563E-9 5.088E-11 A2 [EST] -2.907705647869254E-10 4.205E-11 A3 [EST] -5.202118052475708E-10 1.047E-10 DT [EST] -64.23045561897675 2.672   Orbit Determination Parameters    # obs. used (total)      5420      data-arc span      14398 days (39.42 yr)      first obs. used      1973-09-29      last obs. used      2013-03-01      planetary ephem.      DE405      SB-pert. ephem.      SB405-CPV-2      condition code      0      fit RMS      .62222      data source      ORB      producer      Ryan S. Park      solution date      2013-Mar-03 19:25:29   Additional Information  Earth MOID = 1.01593 AU   T_jup = 2.887  [ show covariance matrix ] [ Ephemeris | Orbit Diagram | Orbital Elements | Physical Parameters | Discovery Circumstances | Close-Approach Data ] Physical Parameter Table Parameter Symbol Value Units Sigma Reference Notes comet total magnitude M1 6.5 mag n/a ICQ 2005 Handbook   comet total magnitude slope K1 14.0   n/a ICQ 2005 Handbook   78P/Gehrels 2          Discovered 1973-Sep-29 by Gehrels, Tom discovered on plate/photo taken on discovery date as well as 9/30, 10/4 Reference: comet.dis Last Updated: 2003-08-29 [ 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 1911-Oct-11 13:52 00:06 Jupiter 0.16409451146878 0.164084327070508 0.16410469627939 4.36204516399825 2.9502278327694 2419321.078385135 6.60434552140117 35.8868771053776 8.79623514333263 43.2462872475054 136905.770334713 T K114/6 CATAB v2.0c-linF95 2013-Mar-03 19:33:34 2013-Mar-03 19:34 1934-Mar-27 07:17 00:01 Jupiter 1.62503979303135 1.6250147166353 1.62506486909038 7.39903012066281 7.32824555940243 2427523.803816237 1.2167938966465 269.781701052428 31.2610814049538 7.47200747341503 164958.400177897 T K114/6 CATAB v2.0c-linF95 2013-Mar-03 19:33:34 2013-Mar-03 19:34 1971-Jun-05 12:27 < 00:01 Jupiter 0.945257109382023 0.94525153659839 0.945262682155704 5.84716926473995 5.69185696580349 2441108.018773948 0.773148605337435 37.599403514034 26.6108475560888 -47.3618251551619 454332.790846136 T K114/6 CATAB v2.0c-linF95 2013-Mar-03 19:33:34 2013-Mar-03 19:34 1995-Feb-06 20:41 < 00:01 Jupiter 0.623125622156486 0.623121416836884 0.6231298274803 5.15174326518342 4.88076155785155 2449755.361896902 0.712359364612928 23.2886602791398 12.653502725388 -48.5218742464209 523537.022948586 T K114/6 CATAB v2.0c-linF95 2013-Mar-03 19:33:34 2013-Mar-03 19:34 2029-Sep-15 14:31 00:02 Jupiter 0.0182553369444244 0.0182532275760228 0.0182574464988666 10.1968757534309 3.34350486524542 2462395.104940405 2.53482140460258 20.2972093446738 8.74475353632134 -74.7019825275981 43794.4198179445 T K114/6 CATAB v2.0c-linF95 2013-Mar-03 19:33:34 2013-Mar-03 19:34 2038-Feb-28 04:24 13:06 Jupiter 1.9258809391183 1.92561522320352 1.92614663847375 3.35027236036886 3.21631839466166 2465482.683995222 786.289606391311 900.170562102596 446.532029413723 3.6426987022863 18039.2920222412 T K114/6 CATAB v2.0c-linF95 2013-Mar-03 19:33:34 2013-Mar-03 19:34 2046-Nov-01 09:23 02:37 Jupiter 0.0895288041731908 0.0871812552160282 0.0918961371645048 5.76569619453276 3.78437106831173 2468650.891322484 157.193270179171 10067.7203277544 94.5738355395858 -32.4838277646896 6603.96710066378 T K114/6 CATAB v2.0c-linF95 2013-Mar-03 19:33:34 2013-Mar-03 19:34 Alternate Designations  Perihelion  Year (est.)  New-Style  Desig Roman  Numeral  Year/  Letter   1990.4       1989 XVII   1989n   1983.2   78P/1981 L1   1981 XVII   1981f   1975.9   78P/1973 S1   1973 XI   1973n  [ Ephemeris | Orbit Diagram | Orbital Elements | Physical Parameters | Discovery Circumstances | Close-Approach Data ] 2013-May-25 15:42 UT (server date/time)   Site Manager:   Donald K. Yeomans Webmaster:   Alan B. Chamberlin