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JPL Small-Body Database Browser
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1810 Epimetheus (4196 P-L)
Classification: Main-belt Asteroid          SPK-ID: 2001810
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 35 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .09226882537638464 3.0097e-08  
a 2.223536783220319 6.0208e-09 au
q 2.018373656051395 6.6068e-08 au
i 4.032232556437283 3.1409e-06 deg
node 254.1084103693271 5.6914e-05 deg
peri 204.4000863558412 6.0965e-05 deg
M 275.1703941497751 2.1794e-05 deg
tp 2459285.871010158234
7.3418e-05 TDB
period 1211.057892198045
n .2972607687206492 1.2074e-09 deg/d
Q 2.428699910389242 6.5763e-09 au
  Orbit Determination Parameters
   # obs. used (total)      2459  
   data-arc span      25272 days (69.19 yr)  
   first obs. used      1950-09-16  
   last obs. used      2019-11-25  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-N16  
   condition code      0  
   norm. resid. RMS      .43862  
   source      ORB  
   producer      Otto Matic  
   solution date      2020-Feb-22 16:05:25  

Additional Information
 Earth MOID = 1.03598 au 
 Jupiter MOID = 2.68914 au 
 T_jup = 3.639 
[ 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 12.6   n/a MPO267714  
diameter diameter 7.669 km 0.162 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (  
rotation period rot_per 28.61 h n/a LCDB (Rev. 2019-August); Warner et al., 2009 Result based on less than full coverage, so that the period may be wrong by 30 percent or so.
Published Reference List:
[Pravec, P.; Wolf, M.; Sarounova, L. (2007)]
geometric albedo albedo 0.274   0.037 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (  

1810 Epimetheus (4196 P-L)          Discovered 1960-Sep-24 by PLS at Palomar
These planets have all been discovered as a result of the Palomar survey of faint minor planets and subsequently identified with planets observed at other oppositions. In Sept. and Oct. 1960, T. Gehrels exposed 130 plates with the 122 cm Schmidt camera at Palomar. In the following years C. J. van Houten and I. van Houten-Groeneveld measured these plates astrometrically and photometrically at Leiden. P. Herget, Cincinnati, computed the orbits of the planets found on the NORC computer, Dahlgren, Virginia, USA.
Note: "planet" implies "minor planet"
Reference: DISCOVERY.DBLast Updated: 2003-08-29

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Alternate Designations
 4196 P-L = 1942 FS = 1950 SC = 1957 WC1 = 1962 GC = 1970 SS 
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]
FirstGov 2020-May-30 18:29 UT
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