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JPL Small-Body Database Browser
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2212 Hephaistos (1978 SB)
Classification: Apollo [NEO]          SPK-ID: 2002212
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 2458600.5 (2019-Apr-27.0) TDB
Reference: JPL 446 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .8377087283680333 2.8209e-08  
a 2.159671478407452 5.4661e-09 au
q .3504958305380348 6.0984e-08 au
i 11.55311488122968 5.7958e-06 deg
node 27.54045234451976 2.0671e-05 deg
peri 209.3813845735305 2.0465e-05 deg
M 284.6685638197617 5.3591e-06 deg
tp 2458843.079285541551
1.793e-05 TDB
period 1159.257638285503
n .3105435652185359 1.179e-09 deg/d
Q 3.968847126276869 1.0045e-08 au
  Orbit Determination Parameters
   # obs. used (total)      2556  
   data-arc span      15034 days (41.16 yr)  
   first obs. used      1978-09-27  
   last obs. used      2019-11-25  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-N16  
   condition code      0  
   norm. resid. RMS      .4258  
   source      ORB  
   producer      Otto Matic  
   solution date      2019-Nov-26 05:03:15  

Additional Information
 Earth MOID = .115947 au 
 Jupiter MOID = 1.16124 au 
 T_jup = 3.099 
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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 13.87   n/a PDS3 (MPC 17264)  
diameter diameter 5.7 km n/a Hazards due to Comets and Asteroids (1994), Ed. T. Gehrels, pp.540-543 based on assumed medium albedo (0.15)
rotation period rot_per 20. h n/a LCDB (Rev. 2019-January); Warner et al., 2009 lower-limit; Result based on fragmentary lightcurve(s), may be completely wrong.
Published Reference List:
[Pravec, P.; Wolf, M.; Sarounova, L.; Mottola, S.; et al. (1997) Icarus 130, 275-286.]
geometric albedo albedo 0.163   0.027 urn:nasa:pds:neowise_diameters_albedos::2.0[neos] (  
B-V BV 0.766   0.037 EAR-A-5-DDR-UBV-MEAN-VALUES-V1.2 #obs=2; phase (min.=15.38, mean=15.38, max.=15.38) deg.
U-B UB 0.397   0.031 EAR-A-5-DDR-UBV-MEAN-VALUES-V1.2 #obs=1; phase=15.38 deg.
Tholen spectral type spec_T SG   n/a EAR-A-5-DDR-TAXONOMY-V4.0 used 2 color indices

2212 Hephaistos           Discovered 1978 Sept. 27 by L. I. Chernykh at the Crimean Astrophysical Observatory.
This Apollo-type object is named for the god of fire and blacksmiths.
NOTE: some special characters may not display properly (any characters within {} are an attempt to place the proper accent above a character)
Reference: MPC 5849Last Updated: 2006-03-21

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