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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 2459000.5 (2020-May-31.0) TDB
Reference: JPL 25 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .4354822610562271 4.4396e-08  
a 2.692183173607968 1.0345e-08 au
q 1.519785157987641 1.1785e-07 au
i 4.834072366681462 4.871e-06 deg
node 212.0867764217125 3.6831e-05 deg
peri 340.9288845645988 3.7e-05 deg
M 258.4094730098043 3.0112e-06 deg
tp 2459455.808803535998
1.5127e-05 TDB
period 1613.449345417592
n .2231244513640588 1.286e-09 deg/d
Q 3.864581189228296 1.4849e-08 au
  Orbit Determination Parameters
   # obs. used (total)      1837  
   data-arc span      22182 days (60.73 yr)  
   first obs. used      1959-03-06  
   last obs. used      2019-11-28  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-N16  
   condition code      0  
   norm. resid. RMS      .48628  
   source      ORB  
   producer      Otto Matic  
   solution date      2020-Feb-22 19:25:11  

Additional Information
 Earth MOID = .520303 au 
 Jupiter MOID = 1.11137 au 
 T_jup = 3.223 
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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 2.53150 h n/a LCDB (Rev. 2019-August); 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.]
[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.]
[Contreras, M.E.; Olguín, L.; Loera-González, P.; Saucedo, J.C.; et al. (2019) Minor Planet Bull. 46, 233-234.]
[Skiff, B.A.; McLelland, K.P.; Sanborn, J.J.; Pravec, P.; Koehn, B.W. (2019) Minor Plantet Bull. 46, 238-265.]

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 ]
FirstGov 2020-Feb-24 18:04 UT
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