+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   2893 Peiroos (1975 QD) Classification: Jupiter Trojan          SPK-ID: 2002893 [ 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 32 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .07735467241888731 4.9054e-08   a 5.145314826772759 7.8684e-08 au q 4.747300683855708 2.9699e-07 au i 14.66437261952795 4.4391e-06 deg node 108.7831184033998 2.0054e-05 deg peri 172.2293392106496 3.9978e-05 deg M 301.1083557756654 3.6612e-05 deg tp 2459697.876864509388 (2022-Apr-28.37686451) 0.00043742 TDB period 4263.010050577616 11.67 9.7787e-05 2.677e-07 d yr n .08444737303662275 1.9371e-09 deg/d Q 5.54332896968981 8.477e-08 au   Orbit Determination Parameters    # obs. used (total)      2338      data-arc span      32001 days (87.61 yr)      first obs. used      1933-01-25      last obs. used      2020-09-06      planetary ephem.      DE431      SB-pert. ephem.      SB431-N16      condition code      0      norm. resid. RMS      .40732      source      ORB      producer      Otto Matic      solution date      2020-Nov-13 04:05:04   Additional Information  Earth MOID = 3.73144 au   Jupiter MOID = .300817 au   T_jup = 2.930  [ 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 9.0   n/a MPO473805 IRAS observations used: 5 diameter diameter 86.884 km 0.954 urn:nasa:pds:neowise_diameters_albedos::2.0[jupiter_trojans] (http://adsabs.harvard.edu/abs/2012ApJ...759...49G)   rotation period rot_per 8.945 h n/a LCDB (Rev. 2020-October); Warner et al., 2009 Published Reference List: [Gonano, M.; Di Martino, M.; Mottola, S.; Neukum, G. (1991) Adv. Space Res. 11, no. 12, 197-200.] [Stephens, R.D.; Coley, D.R.; French, L.M. (2016) Minor Planet Bull. 43, 265-270.] [Stephens, R.D. (2017) Minor Planet Bull. 44, 123-125.] [Stephens, R.D.; Warner, B.D. (2018) Minor Planet Bull. 45, 124-128.] [Stephens, R. D.; Warner, B. D. (2019) MPB 46, 315-317.] [Stephens, R.D.; Warner, B.D. (2020) Minor Planet Bull. 47, 285-289.] geometric albedo albedo 0.048   0.008 urn:nasa:pds:neowise_diameters_albedos::2.0[jupiter_trojans] (http://adsabs.harvard.edu/abs/2012ApJ...759...49G)   B-V BV 0.730   0.030 EAR-A-5-DDR-UBV-MEAN-VALUES-V1.2 #obs=2; phase (min.=10.52, mean=10.54, max.=10.56) deg. U-B UB 0.252   0.083 EAR-A-5-DDR-UBV-MEAN-VALUES-V1.2 #obs=2; phase (min.=10.52, mean=10.54, max.=10.56) deg. Tholen spectral type spec_T D   n/a EAR-A-5-DDR-TAXONOMY-V4.0 used 4 color indices 2893 Peiroos (1975 QD)          Discovered 1975-Aug-30 by Felix Aguilar Observatory at El Leoncito Reference: DISCOVERY.DB Last Updated: 2003-08-29 Alternate Designations  1975 QD = 1933 BJ = 1970 EE = 1979 YV4 = 1981 AP  [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ] 2021-Jan-27 11:31 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin