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65803 Didymos (1996 GT)
Classification: Apollo [NEO, PHA]          SPK-ID: 2065803
Ephemeris | Orbit Diagram | Orbital Elements | Physical Parameters | Discovery Circumstances | Close-Approach Data ]

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Orbit Diagram
Note: Make sure you have Java enabled on your browser to see the applet. This applet is provided as a 3D orbit visualization tool. The applet was implemented using 2-body methods, and hence should not be used for determining accurate long-term trajectories (over several years or decades) or planetary encounter circumstances. For accurate long-term ephemerides, please instead use our Horizons system.

Note: If the applet has stopped working because of a recent Java upgrade, here is a possible workaround.
Orbit Viewer

Additional Notes: the orbits shown in the applet are color coded. The planets are white lines, and the asteroid/comet is a blue line. The bright white line indicates the portion of the orbit that is above the ecliptic plane, and the darker portion is below the ecliptic plane. Likewise for the asteroid/comet orbit, the light blue indicates the portion above the ecliptic plane, and the dark blue the portion below the ecliptic plane.

Orbit Viewer applet originally written and kindly provided by Osamu Ajiki (AstroArts), and further modified by Ron Baalke (JPL).

Orbital Elements at Epoch 2457200.5 (2015-Jun-27.0) TDB
Reference: JPL 120 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .3838655402126658 7.7437e-09  
a 1.644251850408298 9.7322e-09 AU
q 1.013080225605641 1.3624e-08 AU
i 3.407785369247236 2.4234e-06 deg
node 73.22816152281521 1.7038e-05 deg
peri 319.2390586381577 1.8328e-05 deg
M 190.3424879627124 1.8497e-05 deg
tp 2457563.428880408142
4.2778e-05 JED
period 770.1067602489392
n .4674676532947575 4.1503e-09 deg/d
Q 2.275423475210954 1.3468e-08 AU
  Orbit Determination Parameters
   # obs. used (total)      834  
   # delay obs. used      6  
   # Doppler obs. used      0  
   data-arc span      6979 days (19.11 yr)  
   first obs. used      1996-04-11  
   last obs. used      2015-05-21  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-BIG16  
   condition code      0  
   fit RMS      .48673  
   data source      ORB  
   producer      Otto Matic  
   solution date      2015-Jun-04 18:20:59  

Additional Information
 Earth MOID = .0405174 AU 
 T_jup = 4.201 
[ show covariance matrix ]

Ephemeris | Orbit Diagram | Orbital Elements | Physical Parameters | Discovery Circumstances | Close-Approach Data ]

Physical Parameter Table
Parameter Symbol Value Units Sigma Reference Notes
absolute magnitude H 18.0 mag n/a MPO263851  
rotation period rot_per 2.2593 h n/a LCDB (Rev. 2015-July); Warner et al., 2009  
SMASSII spectral type spec_B Xk   n/a Binzel et al. (2004) Meteorit. Planet. Sci. 39, 351-366  

65803 Didymos           Discovered 1996 Apr. 11 by Spacewatch at Kitt Peak.
Greek for "twin", this rapid-rotator Amor possesses a satellite with an orbital period of 11.9 hr. Suspicions arose in the Goldstone delay-Doppler echoes, and these were confirmed with the optical light curve analysis, along with Arecibo radar imaging on 2003 Nov. 23. The name was suggested by J. Montani.
NOTE: some special characters may not display properly (any characters within {} are an attempt to place the proper accent above a character)
Reference: 20040713/MPCPages.arcLast Updated: 2004-07-14

[ show close-approach data ]
Ephemeris | Orbit Diagram | Orbital Elements | Physical Parameters | Discovery Circumstances | Close-Approach Data ]
FirstGov 2015-Dec-01 16:31 UT
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