+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   12P/Pons-Brooks Classification: Halley-type Comet* [NEO]          SPK-ID: 1000068 [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] [ show orbit diagram ] alternate orbits: [epoch=1966-Oct-07.0] 16 (default) [epoch=1884-Jan-25.0] SAO/1884 [epoch=1812-Aug-30.0] SAO/1812 Orbital Elements at Epoch 2439405.5 (1966-Oct-07.0) TDB Reference: JPL 16 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .9542202409863804 1.3375e-07   a 16.99481755725178 1.8461e-06 au q .7780186522514184 2.3102e-06 au i 74.7037493144222 0.00011761 deg node 255.9595132752626 0.00016743 deg peri 199.0936340963835 0.00011895 deg M 63.58443906644973 1.3964e-05 deg tp 2434885.675931168748 (1954-May-23.17593117) 0.00057586 TDB period 25590.17093913168 70.06 0.0041697 1.142e-05 d yr n .01406790133822434 2.2922e-09 deg/d Q 33.21161646225214 3.6077e-06 au Additional Model Parameters  Parameter Value Uncertainty (1-sigma)  A1 [EST] 2.962808270929297E-9 4.007E-10 A2 [EST] -2.711607195758214E-10 1.763E-13   Orbit Determination Parameters    # obs. used (total)      393      data-arc span      75909 days (207.83 yr)      first obs. used      1812-08-18      last obs. used      2020-06-17      planetary ephem.      DE431      SB-pert. ephem.      SB431-N16      condition code      0      norm. resid. RMS      .54267      source      ORB      producer      Davide Farnocchia      solution date      2020-Jun-29 10:49:26   Additional Information  Earth MOID = .183538 au   Jupiter MOID = 2.00157 au   T_jup = 0.591  [ 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 comet total magnitude M1 5.   n/a MPC data tape   comet total magnitude slope K1 15.0   n/a MPC data tape   comet nuclear magnitude M2 11.   n/a MPC data tape   comet nuclear magnitude slope K2 10.0   n/a MPC data tape   12P/Pons-Brooks          Discovered 1812-Jul-21 by Pons, Jean Louis at Marseilles, France Reference: comet.dis Last Updated: 2003-08-29 [ show close-approach data ] Alternate Designations  Perihelion  Year (est.)  New-Style  Desig Roman  Numeral  Year/  Letter   1954.4   12P/1953 M1   1954 VII   1953c   1884.3   12P/1883 R1   1884 I   1883b   1814.3   12P/1812 O1   1812     [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] 2021-Mar-05 10:16 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin