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1495 Helsinki (1938 SW)
Classification: Main-belt Asteroid          SPK-ID: 2001495
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 37 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .1557457396775876 3.7949e-08  
a 2.637654580863564 1.0263e-08 au
q 2.226851117152991 1.0155e-07 au
i 12.72609057373922 4.8492e-06 deg
node 13.08203906270625 1.8837e-05 deg
peri 268.3202448561718 2.4854e-05 deg
M 85.69435602630858 1.5926e-05 deg
tp 2458628.043955094247
(2019-May-24.54395509)
6.924e-05 TDB
period 1564.679196899578
4.28
9.1322e-06
2.5e-08
d
yr
n .2300791118801493 1.3429e-09 deg/d
Q 3.048458044574137 1.1862e-08 au
  Orbit Determination Parameters
   # obs. used (total)      2312  
   data-arc span      32531 days (89.07 yr)  
   first obs. used      1930-12-13  
   last obs. used      2020-01-06  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-N16  
   condition code      0  
   norm. resid. RMS      .3998  
   source      ORB  
   producer      Otto Matic  
   solution date      2020-Jan-28 18:04:20  

Additional Information
 Earth MOID = 1.25544 au 
 Jupiter MOID = 2.21689 au 
 T_jup = 3.345 
[ show covariance matrix ]

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 11.4   n/a MPO435710  
diameter diameter 12.235 km 0.059 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2014ApJ...791..121M)  
rotation period rot_per 5.33116 h n/a LCDB (Rev. 2019-August); Warner et al., 2009 Published Reference List:
[Behrend, R. (2006) Observatoire de Geneve web site, http://obswww.unige.ch/~behrend/page_cou.html]
[Oey, J.; Behrend, R.; Pravec, P.; Teng, J.P.; et al. (2007) Minor Planet Bull. 34, 2.]
[Hanus, J.; Durech, J.; Broz, M.; Marciniak, A.; et al. (2013) Astron. Astrophys. 551, A67.]
geometric albedo albedo 0.274   0.049 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2014ApJ...791..121M)  

1495 Helsinki (1938 SW)          Discovered 1938-Sep-21 by Vaisala, Y. at Turku
Reference: DISCOVERY.DBLast Updated: 2003-08-29

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