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JPL Small-Body Database Browser
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9994 Grotius (4028 P-L)
Classification: Main-belt Asteroid          SPK-ID: 2009994
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 21 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .1759123682401461 3.22e-08  
a 2.585516796800414 1.1743e-08 au
q 2.130692413950577 8.6459e-08 au
i 7.180180722324232 5.3792e-06 deg
node 207.1515256425575 3.2223e-05 deg
peri 224.2353578313879 3.8105e-05 deg
M 346.4011871436655 2.043e-05 deg
tp 2458657.861165699724
8.6412e-05 TDB
period 1518.516349188637
n .2370735094109145 1.6151e-09 deg/d
Q 3.040341179650251 1.3809e-08 au
  Orbit Determination Parameters
   # obs. used (total)      1449  
   data-arc span      21613 days (59.17 yr)  
   first obs. used      1960-09-24  
   last obs. used      2019-11-27  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-N16  
   condition code      0  
   norm. resid. RMS      .50895  
   source      ORB  
   producer      Otto Matic  
   solution date      2019-Dec-03 22:16:21  

Additional Information
 Earth MOID = 1.15124 au 
 Jupiter MOID = 2.28333 au 
 T_jup = 3.389 
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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 14.3   n/a PDS3 (MPC 33669)  
diameter diameter 3.746 km 0.146 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (  
rotation period rot_per 9.219 h n/a LCDB (Rev. 2019-January); 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:
[Waszczak, A.; Chang, C.-K.; Ofeck, E.O.; Laher, F.; et al. (2015) Astron. J. 150, A75.]
geometric albedo albedo 0.263   0.040 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (  

9994 Grotius           Discovered 1960 Sept. 24 by C. J. van Houten and I. van Houten-Groeneveld on Palomar Schmidt plates taken by T. Gehrels.
The works Mare Liberum (1609; "Free Access to the Ocean for all nations") and De Jure Belli ac Pacis (1625; "On the Law of War and Peace") of the Dutch statesman Hugo Grotius (Huig de Groot, 1583-1645) laid the foundation for modern international law.
NOTE: some special characters may not display properly (any characters within {} are an attempt to place the proper accent above a character)
Reference: 20001111/MPCPages.arcLast Updated: 2013-03-29

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Alternate Designations
 4028 P-L = 1981 WH9 
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]
FirstGov 2019-Dec-08 21:51 UT
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