+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   280P/Larsen Classification: Jupiter-family Comet          SPK-ID: 1000492 [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Close-Approach Data ] [ show orbit diagram ] Orbital Elements at Epoch 2454787.5 (2008-Nov-17.0) TDB Reference: JPL 33 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .4180949726414225 6.0767e-07   a 4.511788051435455 7.9816e-07 au q 2.625432149506652 2.4968e-06 au i 11.77968038734452 1.6245e-05 deg node 131.4963398852575 0.00014833 deg peri 104.8350120016027 0.00081537 deg M 169.8047538742992 0.00031596 deg tp 2453136.417381769955 (2004-May-10.91738177) 0.0026554 TDB period 3500.430517998472 9.58 0.00092887 2.543e-06 d yr n .1028444924557012 2.7291e-08 deg/d Q 6.398143953364259 1.1319e-06 au   Orbit Determination Parameters    # obs. used (total)      171      data-arc span      3715 days (10.17 yr)      first obs. used      2004-04-19      last obs. used      2014-06-21      planetary ephem.      DE431      SB-pert. ephem.      SB431-BIG16      condition code      1      norm. resid. RMS      .74712      source      ORB      producer      Otto Matic      solution date      2014-Jul-14 12:04:04   Additional Information  Earth MOID = 1.6466 au   T_jup = 2.809  [ show covariance matrix ] [ 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 11.6   1. 33 from 78 observations, assumed slope, autocmod 2.5c comet total magnitude slope K1 12.   n/a 33 autocmod 2.5c comet nuclear magnitude M2 14.5   01. 33 from 59 observations, autocmod 2.5c comet nuclear magnitude slope K2 5.   n/a 33 autocmod 2.5c comet nuclear phase coefficient PC 0.03   n/a 33 autocmod 2.5c [ show close-approach data ] Alternate Designations  Perihelion  Year (est.)  New-Style  Desig Roman  Numeral  Year/  Letter   2013.9   280P/2013 C1         2004.4   280P/2004 H2        [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Close-Approach Data ] 2021-Mar-07 08:59 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin