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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 ]

[ show orbit diagram ]
Orbital Elements at Epoch 2458600.5 (2019-Apr-27.0) TDB
Reference: JPL 22 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .1759123688818921 3.1921e-08  
a 2.585516796570086 1.1625e-08 au
q 2.130692412101521 8.5578e-08 au
i 7.180180493000865 5.3397e-06 deg
node 207.1515261469158 3.2185e-05 deg
peri 224.2353569454809 3.7991e-05 deg
M 346.4011875927977 2.0228e-05 deg
tp 2458657.861163797574
8.5553e-05 TDB
period 1518.516348985724
n .2370735094425937 1.5988e-09 deg/d
Q 3.04034118103865 1.3669e-08 au
  Orbit Determination Parameters
   # obs. used (total)      1469  
   data-arc span      21622 days (59.20 yr)  
   first obs. used      1960-09-24  
   last obs. used      2019-12-06  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-N16  
   condition code      0  
   norm. resid. RMS      .50683  
   source      ORB  
   producer      Otto Matic  
   solution date      2019-Dec-13 22:57:39  

Additional Information
 Earth MOID = 1.15124 au 
 Jupiter MOID = 2.28333 au 
 T_jup = 3.389 
[ 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 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

[ hide close-approach data ]
Close-Approach Data   ...sorted by Date/Time (TDB)
Date/Time (TDB) Time Uncertainty
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
2022-May-12 23:52 < 00:01 Inter 0.0327920968510727 0.0327908296614441 0.0327933643018911 5.24242635495315 5.24242626979677 2459712.494302423 0.745482934243961 170.068286015447 24.1906376502097 -69.7196102140617 190379.123774583 T 22 CATAB v2.0f-lin.ifort 2019-Dec-13 22:57:49 2019-Dec-13 22:57

Alternate Designations
 4028 P-L = 1981 WH9 
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]
FirstGov 2019-Dec-15 19:15 UT
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