+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   2640 Hallstrom (1941 FN) Classification: Main-belt Asteroid          SPK-ID: 2002640 [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ] [ show orbit diagram ] Orbital Elements at Epoch 2459000.5 (2020-May-31.0) TDB Reference: JPL 33 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .0895950459825693 4.0741e-08   a 2.398130114741509 7.8045e-09 au q 2.18326953683906 9.7255e-08 au i 6.654584114089709 4.1716e-06 deg node 4.448409113879186 2.9069e-05 deg peri 192.269203566765 3.5162e-05 deg M 99.73949852159953 2.0167e-05 deg tp 2458624.686635150107 (2019-May-21.18663515) 7.5803e-05 TDB period 1356.461716284471 3.71 6.6217e-06 1.813e-08 d yr n .2653963585393975 1.2956e-09 deg/d Q 2.612990692643959 8.5037e-09 au   Orbit Determination Parameters    # obs. used (total)      2371      data-arc span      28992 days (79.38 yr)      first obs. used      1941-03-18      last obs. used      2020-08-02      planetary ephem.      DE431      SB-pert. ephem.      SB431-N16      condition code      0      norm. resid. RMS      .44192      source      ORB      producer      Otto Matic      solution date      2020-Aug-24 22:55:02   Additional Information  Earth MOID = 1.18241 au   Jupiter MOID = 2.3466 au   T_jup = 3.513  [ 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 13.0   n/a MPO384774   rotation period rot_per 22.9 h n/a LCDB (Rev. 2019-August); Warner et al., 2009 Result based on fragmentary lightcurve(s), may be completely wrong. Published Reference List: [Hasegawa, S.; Miyasaka, S.; Yoshizumi, C.; Sekiguchi, T.; et al. (2012) arXiv:1204.0548.] SMASSII spectral type spec_B V   n/a EAR-A-5-DDR-TAXONOMY-V4.0 based on a high-resolution spectrum by Xu et al. (1995) or Bus and Binzel (2002) 2640 Hallstrom (1941 FN)          Discovered 1941-Mar-18 by Oterma, L. at Turku Reference: DISCOVERY.DB Last Updated: 2003-08-29 Alternate Designations  1941 FN = 1967 ET = 1976 SG5 = 1978 EM6  [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ] 2020-Oct-25 00:40 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin