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124 Alkeste (A872 QA)
Classification: Main-belt Asteroid          SPK-ID: 2000124
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]

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For accurate long-term ephemerides, please instead use our Horizons system.This orbit viewer was implemented using two-body methods, and hence should not be used for determining accurate long-term trajectories (over several years or decades) or planetary encounter circumstances.


Orbital Elements at Epoch 2459200.5 (2020-Dec-17.0) TDB
Reference: JPL 133 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .07553164178664029 2.8512e-08  
a 2.629800233094822 4.9376e-09 au
q 2.431167103918281 7.6411e-08 au
i 2.957553562779969 4.8469e-07 deg
node 187.974203666149 4.7388e-06 deg
peri 62.24441703234992 1.1158e-05 deg
M 352.6037063733781 1.0063e-05 deg
tp 2459232.503259229025
(2021-Jan-18.00325923)
4.3556e-05 TDB
period 1557.695503188298
4.26
4.387e-06
1.201e-08
d
yr
n .2311106370039269 6.5088e-10 deg/d
Q 2.828433362271364 5.3105e-09 au
  Orbit Determination Parameters
   # obs. used (total)      3611  
   data-arc span      54247 days (148.52 yr)  
   first obs. used      1872-08-24  
   last obs. used      2021-03-03  
   planetary ephem.      DE441  
   SB-pert. ephem.      SB441-N16  
   condition code      0  
   norm. resid. RMS      .48929  
   source      ORB  
   producer      Otto Matic  
   solution date      2021-Apr-12 10:19:58  

Additional Information
 Earth MOID = 1.41728 au 
 Jupiter MOID = 2.18099 au 
 T_jup = 3.395 
[ 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 8.13   n/a E2021B10 IRAS observations used: 12
magnitude slope G 0.19   n/a PDS3 (MPC 17257) Fit
diameter diameter 88.648 km 1.651 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2012ApJ...759L...8M)  
rotation period rot_per 9.906 h n/a LCDB (Rev. 2020-October); Warner et al., 2009 Published Reference List:
[Harris, A.W.; Young, J.W. (1983) Icarus 54, 59-109.]
[Shevchenko, V.G.; Bel'skaya, I.N.; Krugly, Yu.N.; Chiorny, V.G.; Gaftonyuk, N.M. (2002) Icarus 155, 365-374.]
[Behrend, R. (2007) Observatoire de Geneve web site, http://obswww.unige.ch/~behrend/page_cou.html]
[Pilcher, F. (2016) Minor Planet Bull. 43, 296-299.]
geometric albedo albedo 0.128   0.014 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2012ApJ...759L...8M)  
B-V BV 0.844   0.019 EAR-A-5-DDR-UBV-MEAN-VALUES-V1.2 #obs=6; phase (min.=4.53, mean=15.83, max.=22.07) deg.
U-B UB 0.424   0.032 EAR-A-5-DDR-UBV-MEAN-VALUES-V1.2 #obs=6; phase (min.=4.53, mean=14.22, max.=20.37) 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 S   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)

124 Alkeste (A872 QA)          Discovered 1872-Aug-23 by Peters, C. H. F. at Clinton
Reference: DISCOVERY.DBLast Updated: 2003-08-29

[ hide close-approach data ]
Close-Approach Data   ...sorted by Date/Time (TDB)
Date/Time (TDB) Time Uncertainty
(days_HH:MM)
Body Nominal Distance (au) Minimum Distance (au) Maximum Distance (au) V-relative (km/s) V-infinity (km/s) JD (TDB) Time Uncertainty (minutes) Semi-major axis (km) Semi-minor axis (km) range-LOV angle (deg) N-sigma BP Orbit Ref. Reference Modified
1993-Oct-17 10:31 < 00:01 Europ 0.0124368609693557 0.0124359498685472 0.0124377720721134 2.58633890428524 2.58633857385824 2449277.938324931 0.818665849455343 46.1380314390817 17.8881497806467 -11.4344688369315 44505.2873457548 T 133 CATAB v2.0f-lin.ifort 2021-Apr-12 10:21:03 2021-Apr-12 10:21
2042-Oct-25 16:56 < 00:01 Iris 0.0132230361217189 0.0132220511536469 0.0132240211890344 5.64200365075739 5.64200357370103 2467183.205759513 0.320346338458548 94.7677932533098 34.8466284260607 -66.8846582783317 52831.5887299359 T 133 CATAB v2.0f-lin.ifort 2021-Apr-12 10:21:03 2021-Apr-12 10:21
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]
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