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1557 Roehla (1942 AD)
Classification: Main-belt Asteroid          SPK-ID: 2001557
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ]

[ show orbit diagram ]
Orbital Elements at Epoch 2459200.5 (2020-Dec-17.0) TDB
Reference: JPL 44 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .1048878495150898 1.4493e-08  
a 3.01145780962023 1.2104e-08 au
q 2.695592476063741 4.4882e-08 au
i 10.29993343149765 4.0929e-07 deg
node 355.1888242401767 1.0981e-06 deg
peri 3.635168936654238 1.0639e-05 deg
M 153.7171779959533 1.3727e-05 deg
tp 2458385.451403956780
(2018-Sep-23.95140396)
7.0803e-05 TDB
period 1908.81395560933
5.23
1.1508e-05
3.151e-08
d
yr
n .188598788762041 1.137e-09 deg/d
Q 3.327323143176718 1.3373e-08 au
  Orbit Determination Parameters
   # obs. used (total)      2965  
   data-arc span      42911 days (117.48 yr)  
   first obs. used      1903-09-20  
   last obs. used      2021-03-15  
   planetary ephem.      DE441  
   SB-pert. ephem.      SB441-N16  
   condition code      0  
   norm. resid. RMS      .41331  
   source      ORB  
   producer      Otto Matic  
   solution date      2021-Apr-12 12:37:10  

Additional Information
 Earth MOID = 1.69016 au 
 Jupiter MOID = 2.11499 au 
 T_jup = 3.217 
[ 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 11.5   n/a MPO452181  
diameter diameter 18.766 km 0.279 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)  
rotation period rot_per 5.67899 h n/a LCDB (Rev. 2020-October); Warner et al., 2009 sidereal period (not synodic); Result based on less than full coverage, so that the period may be wrong by 30 percent or so.
Published Reference List:
[Durech, J.; Hanus, J.; Oszkiewsicz, D.; Vanco, R. (2016) Astron. Astrophys. 587, A48.]
[Hanus, J.; Delbo, M.; Ali-Lagoa, V.; Bolin, B.; et al. (2016) Astron. Astrophys., submitted.]
[Hanus, J.; Delbo, M.; Ali-Lagoa, V.; Bolin, B.; et al. (2018) Icarus 299, 84-96.]
geometric albedo albedo 0.151   0.037 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)  

1557 Roehla (1942 AD)          Discovered 1942-Jan-14 by Reinmuth, K. at Heidelberg
Reference: DISCOVERY.DBLast Updated: 2003-08-29

Alternate Designations
 1942 AD = 1930 YS = 1950 RF1 = A903 SB 
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ]
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