+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   116 Sirona (A871 RA) Classification: Main-belt Asteroid          SPK-ID: 2000116 [ 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 115 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .1417777804328312 2.8543e-08   a 2.767125481741225 7.6663e-09 au q 2.374808572760825 8.1391e-08 au i 3.563722314066137 3.1457e-07 deg node 63.70715851107187 5.1915e-06 deg peri 94.3763751578889 6.6698e-06 deg M 350.8480702910497 4.5123e-06 deg tp 2459243.241708935055 (2021-Jan-28.74170893) 2.1125e-05 TDB period 1681.286428759579 4.60 6.987e-06 1.913e-08 d yr n .2141217545338786 8.8983e-10 deg/d Q 3.159442390721625 8.7532e-09 au   Orbit Determination Parameters    # obs. used (total)      3052      data-arc span      54136 days (148.22 yr)      first obs. used      1872-12-23      last obs. used      2021-03-13      planetary ephem.      DE441      SB-pert. ephem.      SB441-N16      condition code      0      norm. resid. RMS      .48764      source      ORB      producer      Otto Matic      solution date      2021-Apr-12 10:19:03   Additional Information  Earth MOID = 1.38699 au   Jupiter MOID = 1.82936 au   T_jup = 3.321  [ 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 7.86   n/a E2021B10 IRAS observations used: 5 diameter diameter 71.70 km 5.8 IRAS-A-FPA-3-RDR-IMPS-V6.0 IRAS observations used: 5 rotation period rot_per 12.028 h n/a LCDB (Rev. 2020-October); Warner et al., 2009 Published Reference List: [Zeigler, K.W.; Florence, W.B. (1985) Icarus 62, 512-517.] [Durech, J.; Hanus, J.; Oszkiewsicz, D.; Vanco, R. (2016) Astron. Astrophys. 587, A48.] geometric albedo albedo 0.2560   0.047 IRAS-A-FPA-3-RDR-IMPS-V6.0 IRAS observations used: 5 B-V BV 0.873   0.073 EAR-A-5-DDR-UBV-MEAN-VALUES-V1.2 #obs=2; phase (min.=5.71, mean=12.00, max.=18.29) deg. U-B UB 0.429   0.030 EAR-A-5-DDR-UBV-MEAN-VALUES-V1.2 #obs=2; phase (min.=5.71, mean=12.00, max.=18.29) deg. Tholen spectral type spec_T S   n/a EAR-A-5-DDR-TAXONOMY-V4.0 used 7 color indices; used ground-based radiometric albedo SMASSII spectral type spec_B Sk   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) 116 Sirona (A871 RA)          Discovered 1871-Sep-08 by Peters, C. H. F. at Clinton Reference: DISCOVERY.DB Last Updated: 2003-08-29 [ show close-approach data ] Alternate Designations  A871 RA = 1954 UC3 = 1998 EK13 = 1998 ES21  [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] 2021-Apr-23 00:20 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin