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18707 Annchi (1998 HO96)
Classification: Main-belt Asteroid          SPK-ID: 2018707
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ]

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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 26 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .1886880977742874 5.3621e-08  
a 2.554197339477386 1.1656e-08 au
q 2.072250702151252 1.4031e-07 au
i 6.843885316546534 4.3937e-06 deg
node 64.50335471626248 5.3842e-05 deg
peri 62.7876498242509 5.6513e-05 deg
M 216.5910773875544 1.5382e-05 deg
tp 2459594.455312970782
(2022-Jan-14.95531297)
6.3247e-05 TDB
period 1491.008430816598
4.08
1.0206e-05
2.794e-08
d
yr
n .241447326895955 1.6527e-09 deg/d
Q 3.036143976803519 1.3855e-08 au
  Orbit Determination Parameters
   # obs. used (total)      1287  
   data-arc span      9589 days (26.25 yr)  
   first obs. used      1994-05-01  
   last obs. used      2020-08-01  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-N16  
   condition code      0  
   norm. resid. RMS      .52787  
   source      ORB  
   producer      Otto Matic  
   solution date      2020-Aug-25 01:22:07  

Additional Information
 Earth MOID = 1.09803 au 
 Jupiter MOID = 2.06376 au 
 T_jup = 3.403 
[ show covariance matrix ]

Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ]

Physical Parameter Table
Parameter Symbol Value Units Sigma Reference Notes
absolute magnitude H 14.4   n/a MPO340832  
diameter diameter 3.238 km 0.029 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)  
geometric albedo albedo 0.352   0.036 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)  

18707 Annchi           Discovered 1998 Apr. 21 by the Lincoln Laboratory Near-Earth Asteroid Research Team at Socorro.
Ann Chi (b. 1986) is a finalist in the 2004 Intel Science Talent Search, a science competition for high school seniors. She was also awarded third place in the 2003 Intel International Science and Engineering Fair for her chemistry project. She attends the Terre Haute South Vigo High School, Terre Haute, Indiana.
NOTE: some special characters may not display properly (any characters within {} are an attempt to place the proper accent above a character)
Reference: 20040415/MPCPages.arcLast Updated: 2004-04-20
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ]
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