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JPL Small-Body Database Browser
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9671 Hemera (1997 TU9)
Classification: Mars-crossing Asteroid          SPK-ID: 2009671
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.


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Orbital Elements at Epoch 2458600.5 (2019-Apr-27.0) TDB
Reference: JPL 23 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .4358789652914559 4.457e-08  
a 2.691388396922687 1.0395e-08 au
q 1.518268807274596 1.1823e-07 au
i 4.835632632750958 4.8789e-06 deg
node 212.0856744662356 3.759e-05 deg
peri 340.9464764690251 3.777e-05 deg
M 169.1285574136403 2.7673e-06 deg
tp 2457842.834636045400
(2017-Mar-30.33463605)
1.1308e-05 TDB
period 1612.734923035876
4.42
9.3436e-06
2.558e-08
d
yr
n .2232232928411581 1.2933e-09 deg/d
Q 3.864507986570779 1.4926e-08 au
  Orbit Determination Parameters
   # obs. used (total)      1814  
   data-arc span      22151 days (60.65 yr)  
   first obs. used      1959-03-06  
   last obs. used      2019-10-28  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-N16  
   condition code      0  
   norm. resid. RMS      .49016  
   source      ORB  
   producer      Otto Matic  
   solution date      2019-Nov-07 03:18:38  

Additional Information
 Earth MOID = .519147 au 
 Jupiter MOID = 1.1126 au 
 T_jup = 3.223 
[ 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 13.9   n/a MPO309226  
rotation period rot_per 2.53143 h n/a LCDB (Rev. 2019-January); Warner et al., 2009 Published Reference List:
[Brincat, S.A. (2017) Minor Planet Bull. 44, 199-200.]
[Salvaggio, F.; Marchini A.; Papini, R. (2017) Minor Planet Bull. 44, 248-249.]
[Skiff, B.A. (2017) Posting on CALL web site: http://www.minorplanet.info/call.html]
[Aznar Macias, A.; Cornea, R.; Suciu, O. (2018) Minor Planet Bull. 45, 92-96.]
[Ditteon, R.; Young, J. (2018) Minor Planet Bull. 45, 117-119.]
[Mas, V.; Fornas, G.; Lozano, J.; Rodrigo, O.; et al. (2018) Minor Planet Bull. 45, 76-82.]

9671 Hemera           Discovered 1997 Oct. 5 by L. Sarounova at Ondrejov.
The Greek goddess of bright day, daughter of goddess of night Nykta and god of darkness Erebus, Hemera, meaning `day' in Greek, gives rise to the word "ephemeris".
NOTE: some special characters may not display properly (any characters within {} are an attempt to place the proper accent above a character)
Reference: 20010109/MPCPages.arcLast Updated: 2009-05-11

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Alternate Designations
 1997 TU9 = 1959 EY = 1986 LV 
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]
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