+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   1555 Dejan (1941 SA) Classification: Main-belt Asteroid          SPK-ID: 2001555 [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] [ show orbit diagram ] Orbital Elements at Epoch 2459000.5 (2020-May-31.0) TDB Reference: JPL 38 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .276140276636951 3.2303e-08   a 2.691081583412597 7.9066e-09 au q 1.947965570516438 8.79e-08 au i 6.020622409485523 3.5393e-06 deg node 318.0378444025134 3.354e-05 deg peri 47.59621642591394 3.3977e-05 deg M 295.6202083080109 7.0331e-06 deg tp 2459288.860512978433 (2021-Mar-15.36051298) 3.2259e-05 TDB period 1612.459157508474 4.41 7.1063e-06 1.946e-08 d yr n .2232614688711011 9.8393e-10 deg/d Q 3.434197596308755 1.009e-08 au   Orbit Determination Parameters    # obs. used (total)      2725      data-arc span      32249 days (88.29 yr)      first obs. used      1932-08-01      last obs. used      2020-11-16      planetary ephem.      DE431      SB-pert. ephem.      SB431-N16      condition code      0      norm. resid. RMS      .41861      source      ORB      producer      Otto Matic      solution date      2020-Dec-18 02:01:19   Additional Information  Earth MOID = .951907 au   Jupiter MOID = 2.06684 au   T_jup = 3.308  [ 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 11.6   n/a MPO435711   diameter diameter 23.199 km 0.314 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)   rotation period rot_per 16.960 h n/a LCDB (Rev. 2020-October); Warner et al., 2009 Result based on less than full coverage, so that the period may be wrong by 30 percent or so. Published Reference List: [Brines, P.; Lozano, J.; Rodrigo, O.; Fornas, A.; et al. (2017) Minor Planet Bull. 44, 145-149.] geometric albedo albedo 0.053   0.006 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)   1555 Dejan (1941 SA)          Discovered 1941-Sep-15 by Rigaux, F. at Uccle Reference: DISCOVERY.DB Last Updated: 2003-08-29 [ show close-approach data ] Alternate Designations  1941 SA = 1932 PC = 1934 CD1 = 1954 NJ  [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] 2021-Jan-19 09:57 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin