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JPL Small-Body Database Browser
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18499 Showalter (1996 MR)
Classification: Mars-crossing Asteroid          SPK-ID: 2018499
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]

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Orbital Elements at Epoch 2458600.5 (2019-Apr-27.0) TDB
Reference: JPL 12 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .3494135257668701 4.1046e-08  
a 2.391991740776712 1.0346e-08 au
q 1.556197473026688 9.8852e-08 au
i 4.284542620188219 4.8216e-06 deg
node 134.6142819383203 7.0099e-05 deg
peri 193.3371602347023 7.0575e-05 deg
M 52.33628905781979 1.2314e-05 deg
tp 2458404.056182512678
(2018-Oct-12.55618251)
4.5192e-05 TDB
period 1351.256949404772
3.70
8.7665e-06
2.4e-08
d
yr
n .2664186113222802 1.7284e-09 deg/d
Q 3.227786008526736 1.3961e-08 au
  Orbit Determination Parameters
   # obs. used (total)      551  
   data-arc span      8654 days (23.69 yr)  
   first obs. used      1995-03-01  
   last obs. used      2018-11-09  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-N16  
   condition code      0  
   norm. resid. RMS      .58296  
   source      ORB  
   producer      Otto Matic  
   solution date      2019-Jul-12 22:39:59  

Additional Information
 Earth MOID = .544279 au 
 Jupiter MOID = 2.13702 au 
 T_jup = 3.442 
[ 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 15.8   n/a MPO452433  

18499 Showalter           Discovered 1996 June 22 by NEAT at Haleakala.
Mark R. Showalter (b. 1957), planetary scientist at the SETI Institute, is (co-)discover of the Jovian gossamer ring, Saturnian moon Pan, Uranian moons Mab and Cupid, two faint Uranian rings, Neptunian moon S/2004 N 1, and Plutonian moons Kerberos and Styx. He is the leader of the Planetary Data Systems Rings Node.
NOTE: some special characters may not display properly (any characters within {} are an attempt to place the proper accent above a character)
Reference: MPC batch dated 2014-09-09Last Updated: 2014-11-10

[ show close-approach data ]
Alternate Designations
 1996 MR = 1995 FW6 
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]
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