+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   4057 Demophon (1985 TQ) Classification: Jupiter Trojan          SPK-ID: 2004057 [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ] [ show orbit diagram ] Orbital Elements at Epoch 2459200.5 (2020-Dec-17.0) TDB Reference: JPL 36 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .1200211864098761 2.6192e-08   a 5.254987374708869 7.7762e-08 au q 4.62427755542739 1.8563e-07 au i 2.871984336679064 1.6927e-06 deg node 24.28885913479728 1.1773e-05 deg peri 59.24505341411014 2.9468e-05 deg M 279.188610728435 2.5543e-05 deg tp 2460188.202185087639 (2023-Aug-31.70218509) 0.00032583 TDB period 4400.033087374048 12.05 9.7665e-05 2.674e-07 d yr n .0818175665617208 1.8161e-09 deg/d Q 5.885697193990348 8.7095e-08 au   Orbit Determination Parameters    # obs. used (total)      2219      data-arc span      12903 days (35.33 yr)      first obs. used      1985-09-22      last obs. used      2021-01-19      planetary ephem.      DE441      SB-pert. ephem.      SB441-N16      condition code      0      norm. resid. RMS      .48248      source      ORB      producer      Otto Matic      solution date      2021-Apr-12 15:53:25   Additional Information  Earth MOID = 3.64113 au   Jupiter MOID = .0694116 au   T_jup = 2.983  [ show covariance matrix ] [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ] Physical Parameter Table Parameter Symbol Value Units Sigma Reference Notes absolute magnitude H 10.26   n/a E2021B10   diameter diameter 45.683 km 6.581 urn:nasa:pds:neowise_diameters_albedos::2.0[jupiter_trojans] (http://adsabs.harvard.edu/abs/2012ApJ...759...49G)   rotation period rot_per 29.82 h n/a LCDB (Rev. 2020-October); Warner et al., 2009 Published Reference List: [Mottola, S.; Di Martino, M.; Erikson, A.; Gonano-Beurer, M.; et al. (2011) Astron. J. 141, A170.] [Ryan, E.L.; Sharkey, B.N.L.; Woodward, C.E. (2017) Astron. J. 153, A116.] [Szabo, Gy.M.; Pal, A.; Kiss, Cs.; Kiss, L.L.; et al. (2017) Astron. Astrophys. 599, A44.] geometric albedo albedo 0.077   0.015 urn:nasa:pds:neowise_diameters_albedos::2.0[jupiter_trojans] (http://adsabs.harvard.edu/abs/2012ApJ...759...49G)   4057 Demophon (1985 TQ)          Discovered 1985-Oct-15 by Bowell, E. at Flagstaff Reference: DISCOVERY.DB Last Updated: 2003-08-29 [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ] 2021-May-19 00:20 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin