+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   3361 Orpheus (1982 HR) Classification: Apollo [NEO, PHA]          SPK-ID: 2003361 [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] [ show orbit diagram ] Orbital Elements at Epoch 2455844.5 (2011-Oct-10.0) TDB Reference: JPL 132 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .3227518287938224 3.7127e-08   a 1.209662179045708 1.1101e-09 au q .8192414985359853 4.5113e-08 au i 2.685064208145241 4.0392e-06 deg node 189.5305495453812 4.38e-05 deg peri 301.6952073346065 4.4104e-05 deg M 102.8299018073053 7.9289e-06 deg tp 2455705.692957596580 (2011-May-24.19295760) 1.0813e-05 TDB period 485.9533500175061 1.33 6.6891e-07 1.831e-09 d yr n .7408118495057834 1.0197e-09 deg/d Q 1.60008285955543 1.4683e-09 au Additional Model Parameters  Parameter Value Uncertainty (1-sigma)  A2 [EST] 2.095597614176399E-14 2.915E-15 ALN [SET] 1. n/a NK [SET] 0. n/a NM [SET] 2. n/a R0 [SET] 1. n/a   Orbit Determination Parameters    # obs. used (total)      870      data-arc span      13173 days (36.07 yr)      first obs. used      1982-04-24      last obs. used      2018-05-18      planetary ephem.      DE431      SB-pert. ephem.      SB431-N16      condition code      0      norm. resid. RMS      .47356      source      ORB      producer      Otto Matic      solution date      2019-Jan-14 15:11:50   Additional Information  Earth MOID = .0135908 au   Jupiter MOID = 3.45075 au   T_jup = 5.213   Nongravitational accels. using nonstandard g(r) = (1 au/ r)^2  [ 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 absolute magnitude H 19.03   n/a PDS3 (MPC 17268)   diameter diameter 0.3 km n/a Hazards due to Comets and Asteroids (1994), Ed. T. Gehrels, pp.540-543 based on assumed light albedo (0.40) rotation period rot_per 3.5327 h n/a LCDB (Rev. 2020-October); Warner et al., 2009 Published Reference List: [Wisniewski, W.Z. (1991) Icarus 90, 117-122.] [Polishook, D. (2012) Minor Planet Bull. 39, 187-192.] [Pravec, P.; Wolf, M.; Sarounova, L. (2019) http://www.asu.cas.cz/~ppravec/neo.htm] [Skiff, B.A.; McLelland, K.P.; Sanborn, J.J.; Pravec, P.; Koehn, B.W. (2019) Minor Plantet Bull. 46, 238-265.] [Troianskyi, V.; Kashuba, V.; Krugly, Yu. (2019) Minor Planet Bull. 46, 109-111.] [Díaz-Vachier, I.; Cotto-Figueroa, D. (2020) Minor Planet Bull. 47, 149-150.] geometric albedo albedo 0.357   0.135 urn:nasa:pds:neowise_diameters_albedos::2.0[neos] (http://adsabs.harvard.edu/abs/2011ApJ...743..156M)   B-V BV 1.022   0.020 EAR-A-5-DDR-UBV-MEAN-VALUES-V1.2 #obs=1; phase=24.51 deg. U-B UB 0.503   0.039 EAR-A-5-DDR-UBV-MEAN-VALUES-V1.2 #obs=1; phase=24.51 deg. 3361 Orpheus (1982 HR)          Discovered 1982-Apr-24 by Torres, C. at Cerro El Roble Reference: DISCOVERY.DB Last Updated: 2003-08-29 [ show close-approach data ] [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] 2021-Jan-17 20:04 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin