+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   1375 Alfreda (1935 UB) Classification: Main-belt Asteroid          SPK-ID: 2001375 [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] [ show orbit diagram ] Orbital Elements at Epoch 2459200.5 (2020-Dec-17.0) TDB Reference: JPL 44 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .07123348768714341 2.9483e-08   a 2.447582402795069 6.9161e-09 au q 2.273232571842297 7.3091e-08 au i 5.819252658034546 3.5651e-06 deg node 52.75805253173157 3.8446e-05 deg peri 32.7034621051419 4.9938e-05 deg M 47.49459732723464 3.0993e-05 deg tp 2459015.978864183528 (2020-Jun-15.47886418) 0.00012042 TDB period 1398.635058136152 3.83 5.9282e-06 1.623e-08 d yr n .2573938054146468 1.091e-09 deg/d Q 2.62193223374784 7.4088e-09 au   Orbit Determination Parameters    # obs. used (total)      2897      data-arc span      32609 days (89.28 yr)      first obs. used      1931-10-12      last obs. used      2021-01-21      planetary ephem.      DE431      SB-pert. ephem.      SB431-N16      condition code      0      norm. resid. RMS      .40571      source      ORB      producer      Otto Matic      solution date      2021-Feb-24 00:54:49   Additional Information  Earth MOID = 1.29115 au   Jupiter MOID = 2.51877 au   T_jup = 3.487  [ 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 11.52   n/a E2021B10   diameter diameter 13.928 km 0.174 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2014ApJ...791..121M)   rotation period rot_per 19.14 h n/a LCDB (Rev. 2020-October); Warner et al., 2009 Published Reference List: [Pligge, Z.; Monnier, A.; Pharo, J.; Stolze, K.; Yim, A.; Ditteon, R. (2011) Minor Planet Bull. 38, 5-7.] geometric albedo albedo 0.204   0.021 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2014ApJ...791..121M)   1375 Alfreda (1935 UB)          Discovered 1935-Oct-22 by Delporte, E. at Uccle Reference: DISCOVERY.DB Last Updated: 2003-08-29 [ show close-approach data ] Alternate Designations  1935 UB = 1931 TV3 = 1933 FC = A916 WK  [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] 2021-Feb-27 20:05 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin