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JPL Small-Body Database Browser
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1656 Suomi (1942 EC)
Classification: Mars-crossing Asteroid          SPK-ID: 2001656
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 2458600.5 (2019-Apr-27.0) TDB
Reference: JPL 29 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .1233708263767845 3.7295e-08  
a 1.877492709482589 4.3538e-09 au
q 1.645864882397333 6.9948e-08 au
i 25.06612180197548 4.6518e-06 deg
node 175.5636297362088 9.8367e-06 deg
peri 287.3671017848304 2.0724e-05 deg
M 44.6358210917013 1.9624e-05 deg
tp 2458483.994388634935
5.1153e-05 TDB
period 939.6493458752884
n .3831216416850246 1.3327e-09 deg/d
Q 2.109120536567844 4.8909e-09 au
  Orbit Determination Parameters
   # obs. used (total)      2037  
   data-arc span      28187 days (77.17 yr)  
   first obs. used      1942-03-10  
   last obs. used      2019-05-12  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-N16  
   condition code      0  
   norm. resid. RMS      .37496  
   source      ORB  
   producer      Otto Matic  
   solution date      2019-May-29 19:25:53  

Additional Information
 Earth MOID = .754383 au 
 Jupiter MOID = 3.03297 au 
 T_jup = 3.851 
[ 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 12.8   n/a MPO425817  
diameter diameter 7.86 km 0.7 IRAS-A-FPA-3-RDR-IMPS-V6.0 IRAS observations used: 3
rotation period rot_per 2.583 h n/a LCDB (Rev. 2019-January); Warner et al., 2009 Published Reference List:
[Stephens, R.D. (2004) Minor Planet Bull. 31, 95-97.]
[Brinsfield, J.W. (2008) Minor Planet Bull. 35, 23-24.]
[Warner, B.D. (2009) Minor Planet Bull. 36, 109-116.]
[Warner, B.D. (2012) Minor Planet Bull. 39, 245-252.]
[Warner, B.D. (2014) Minor Planet Bull. 41, 144-155.]
[Warner, B.D. (2016) Minor Planet Bull. 43, 57-65.]
[Warner, B.D. (2017) Minor Planet Bull. 44, 289-294.]
geometric albedo albedo 0.1556   0.032 IRAS-A-FPA-3-RDR-IMPS-V6.0 IRAS observations used: 3
Tholen spectral type spec_T S   n/a EAR-A-5-DDR-TAXONOMY-V4.0 based on a medium resolution spectrum published by Chapman and Gaffey (1979)

1656 Suomi (1942 EC)          Discovered 1942-Mar-11 by Vaisala, Y. at Turku
Reference: DISCOVERY.DBLast Updated: 2003-08-29

Alternate Designations
 1942 EC = 1955 HL 
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ]
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