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JPL Small-Body Database Browser
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5573 Hilarydownes (1981 QX)
Classification: Main-belt Asteroid          SPK-ID: 2005573
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]

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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 33 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .2905096950821559 3.0638e-08  
a 2.591994115341024 9.9922e-09 au
q 1.838994695238561 8.1343e-08 au
i 11.20245883534829 4.4255e-06 deg
node 178.3213948810777 2.146e-05 deg
peri 103.6570195136398 2.3314e-05 deg
M 131.4605800804094 1.065e-05 deg
tp 2458443.900916061706
4.2981e-05 TDB
period 1524.226274486417
n .2361854050320061 1.3658e-09 deg/d
Q 3.344993535443488 1.2895e-08 au
  Orbit Determination Parameters
   # obs. used (total)      1769  
   data-arc span      23686 days (64.85 yr)  
   first obs. used      1955-03-24  
   last obs. used      2020-01-28  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-N16  
   condition code      0  
   norm. resid. RMS      .48667  
   source      ORB  
   producer      Otto Matic  
   solution date      2020-Feb-22 17:41:15  

Additional Information
 Earth MOID = .861892 au 
 Jupiter MOID = 1.98431 au 
 T_jup = 3.332 
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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 13.8   n/a MPO302098  
diameter diameter 10.015 km 0.058 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (  
rotation period rot_per 10.685 h n/a LCDB (Rev. 2019-August); 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:
[Behrend, R. (2006) Observatoire de Geneve web site,]
geometric albedo albedo 0.097   0.007 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (  

5573 Hilarydownes           Discovered 1981 Aug. 24 by A. Mrkos at Klet.
Hilary Downes (b. 1954) is a planetary petrologist at Birkbeck College London. She is a terrestrial mantle expert, and her planetary science research seeks to understand the geological evolution of the ureilite meteorite parent body.
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 2018-05-29Last Updated: 2018-09-17

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Alternate Designations
 1981 QX = 1989 KL = A913 CG 
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]
FirstGov 2020-Apr-03 01:56 UT
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