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

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Orbital Elements at Epoch 2459000.5 (2020-May-31.0) TDB
Reference: JPL 147 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .3836383357953901 9.7517e-09  
a 1.644576707340323 5.6956e-09 au
q 1.013654036248419 1.7955e-08 au
i 3.407819057354463 3.0891e-06 deg
node 73.20696104203657 2.3229e-05 deg
peri 319.3018682344476 2.5553e-05 deg
M 311.5778279424352 1.6314e-05 deg
tp 2459104.114705039489
(2020-Sep-11.61470504)
3.5445e-05 TDB
period 770.3349979813357
2.11
4.0018e-06
1.096e-08
d
yr
n .4673291502312379 2.4277e-09 deg/d
Q 2.275499378432227 7.8807e-09 au
  Orbit Determination Parameters
   # obs. used (total)      932  
   # delay obs. used      6  
   # Doppler obs. used      0  
   data-arc span      8413 days (23.03 yr)  
   first obs. used      1996-04-11  
   last obs. used      2019-04-24  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-N16  
   condition code      0  
   norm. resid. RMS      .32651  
   source      ORB  
   producer      Davide Farnocchia  
   solution date      2019-May-08 10:45:04  

Additional Information
 Earth MOID = .0406512 au 
 Jupiter MOID = 3.16587 au 
 T_jup = 4.200 
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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 18.0   n/a MPO412594  
diameter diameter 0.78 km 0.08 Richardson et al., 2016, "Dynamical and Physical Properties of 65803 Didymos", LPSC Abstract (submitted) uncertainty is published as "10%"
bulk density density 2.1 g/cm^3 0.6 Richardson et al., 2016, "Dynamical and Physical Properties of 65803 Didymos", LPSC Abstract (submitted) uncertainty is published as "30%"
rotation period rot_per 2.2593 h n/a LCDB (Rev. 2019-August); Warner et al., 2009 Published Reference List:
[Pravec, P.; et al. (2003) IAUC 8244. (65803)]
[Kitazato, K.; Abe, M.; Mito, H. (2005) Asia-Oceana Geophys. Soc. abstract 58-PS-A1183.]
[Pravec, P.; et al. (2006) Icarus 181, 63-93.]
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

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