+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   C/2021 A1 (Leonard) Classification: Hyperbolic Comet          SPK-ID: 1003751 [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Close-Approach Data ] [ show orbit diagram ] Orbital Elements at Epoch 2459241.5 (2021-Jan-27.0) TDB Reference: JPL 5 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e 1.000086449327069 9.8356e-06   a -7114.254678753327 809.41 au q .6150225295751119 8.0396e-06 au i 132.6861300357353 3.3469e-05 deg node 255.8762605718946 0.00054178 deg peri 225.0880527619856 0.00069176 deg M -.0005605641507650001 9.5659e-05 deg tp 2459582.783552367617 (2022-Jan-03.28355237) 0.0045246 TDB period n/a n/a n/a n/a d yr n 1.642517334562853E-6 2.8031e-07 deg/d Q n/a n/a au   Orbit Determination Parameters    # obs. used (total)      509      data-arc span      348 days      first obs. used      2020-04-11      last obs. used      2021-03-25      planetary ephem.      DE441      SB-pert. ephem.      SB441-N16      norm. resid. RMS      .49064      source      ORB      producer      Otto Matic      solution date      2021-Apr-15 23:34:17   Additional Information  Earth MOID = .230638 au   Jupiter MOID = .296522 au  [ hide covariance matrix ] Orbit Covariance (6×6)   e q tp node peri i e 9.673869785817926E-11 -3.243961741982307E-12 -4.250224717411152E-8 2.964016640215804E-9 -5.04292604650748E-9 1.300759928041545E-10 q -3.243961741982307E-12 6.463569904674049E-11 1.075661017554942E-8 -1.402134557181138E-9 -2.836524173201051E-9 -1.432055206318245E-10 tp -4.250224717411152E-8 1.075661017554942E-8 2.047245088865446E-5 -1.601819949210413E-6 1.724521290640529E-6 -8.968213370404112E-8 node 2.964016640215804E-9 -1.402134557181138E-9 -1.601819949210413E-6 2.935275487818524E-7 2.107776140537031E-8 1.490512233431597E-8 peri -5.04292604650748E-9 -2.836524173201051E-9 1.724521290640529E-6 2.107776140537031E-8 4.785356004298582E-7 4.665266066771898E-9 i 1.300759928041545E-10 -1.432055206318245E-10 -8.968213370404112E-8 1.490512233431597E-8 4.665266066771898E-9 1.120152887723618E-9 [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Close-Approach Data ] Physical Parameter Table Parameter Symbol Value Units Sigma Reference Notes comet total magnitude M1 7.9   0.5 5 2 parameter fit from 441 observations, autocmod 2.9c comet total magnitude slope K1 11.25   n/a 5 autocmod 2.9c comet nuclear magnitude M2 12.5   0.3 5 from 21 observations, autocmod 2.9c comet nuclear magnitude slope K2 5.   n/a 5 autocmod 2.9c comet nuclear phase coefficient PC 0.03   n/a 5 autocmod 2.9c [ 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 2021-Dec-12 13:54 00:12 Earth 0.233374039577333 0.233339415053154 0.233408705403054 70.6706321103683 70.6704705550223 2459561.079407995 11.9791535165275 5837.56102742631 826.991842421479 -74.7824643298701 40699.8484446841 T 5 CATAB v2.0g-lin.ifort 2021-Apr-15 23:34:18 2021-Apr-15 23:34 2021-Dec-18 02:09 00:11 Venus 0.028497520840727 0.0283637454176876 0.028631302930376 78.2325312597717 78.2315572188859 2459566.589828475 10.8215900770931 6706.92216236491 864.545806583154 5.98238948367356 810.061952993684 T 5 CATAB v2.0g-lin.ifort 2021-Apr-15 23:34:18 2021-Apr-15 23:34 [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Close-Approach Data ] 2021-Apr-22 00:47 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin