+ View the NASA Portal + Near-Earth Object (NEO) Program Search JPL JPL Small-Body Database Browser Search: [ help ]   4660 Nereus (1982 DB) Classification: Apollo [NEO, PHA]          SPK-ID: 2004660 [ Ephemeris | Orbit Diagram | Orbital Elements | Physical Parameters | Discovery Circumstances | Close-Approach Data ] [ show orbit diagram ] Orbital Elements at Epoch 2456400.5 (2013-Apr-18.0) TDB Reference: JPL 91 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .3600017301563176 3.3593e-09   a 1.488664444391508 3.0005e-09 AU q .9527426687883721 4.5328e-09 AU i 1.431870851663859 2.8314e-06 deg node 314.4652859472974 3.2947e-05 deg peri 157.9874825916469 3.4106e-05 deg M 71.19488521750874 7.3214e-06 deg tp 2456269.298154525868 (2012-Dec-07.79815453) 1.3098e-05 JED period 663.4277761160264 1.82 2.0058e-06 5.492e-09 d yr n .5426363094225345 1.6406e-09 deg/d Q 2.024586219994645 4.0807e-09 AU   Orbit Determination Parameters    # obs. used (total)      534      # delay obs. used      16      # Doppler obs. used      16      data-arc span      11519 days (31.54 yr)      first obs. used      1981-09-30      last obs. used      2013-04-14      planetary ephem.      DE405      SB-pert. ephem.      SB405-CPV-2      condition code      0      fit RMS      .46205      data source      ORB      producer      Otto Matic      solution date      2013-Apr-29 13:12:37   Additional Information  Earth MOID = .00325957 AU   T_jup = 4.493  [ show covariance matrix ] [ Ephemeris | Orbit Diagram | Orbital Elements | Physical Parameters | Discovery Circumstances | Close-Approach Data ] Physical Parameter Table Parameter Symbol Value Units Sigma Reference Notes absolute magnitude H 18.2 mag n/a MPO190132   diameter diameter 0.33 km n/a Delbo et al. (2003). Icarus, v. 166, pp. 116-130   rotation period rot_per 15.1 h n/a Asteroid Lightcurve DataBase (Rev. 2013-May-01) Result based on less than full coverage, so that the period may be wrong by 30 percent or so. Published Reference List: [Ishibashi, Y.; Abe, M.; Takagi, Y. (1998) Lunar and Planetary Sci. XVIX. CD-ROM, Houston: Lunar & Planetary Inst.] [Ishibashi, Y.; Abe, M.; Takagi, Y. (2000) Adv. Space Res. 25, 277-280.] [Brozovic, M.; Ostro, S.J.; Benner, L.A.M.; Giorgini, J.D.; et al. (2009) Icarus 201, 153-166.] geometric albedo albedo 0.55   n/a Delbo et al. (2003). Icarus, v. 166, pp. 116-130   SMASSII spectral type spec_B Xe   n/a Binzel et al. (2004) Planet. Space Sci. 52, 291-296   4660 Nereus (1982 DB)          Discovered 1982-Feb-28 by Helin, E. F. at Palomar (675) Reference: DISCOVERY.DB Last Updated: 2003-08-29 [ show close-approach data ] [ Ephemeris | Orbit Diagram | Orbital Elements | Physical Parameters | Discovery Circumstances | Close-Approach Data ] 2013-May-23 09:31 UT (server date/time)   Site Manager:   Donald K. Yeomans Webmaster:   Alan B. Chamberlin