Question re. Luna-4 / Lunik-IV

Date: Sun Oct 31 2010 - 21:17:07 UTC

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    On May 16 this year asteroid 2010 KQ was discovered by the Catalina Sky 
    Survey but which later was shown to be an artificial object in orbit around 
    the Sun.  Once it was evident it was not a natural body its designation was 
    withdrawn and it was reassigned the original descriptor given to it by the 
    CSS, namey RK252A5.
    With the help of Bill Gray it has been possible to narrow down the 
    possibilities as to the identity of this object.  Earlier today thanks to 
    information provided by Joshua Hopkins it has been possible to rule out one 
    of the remaining possibilities (the Helios-A Centaur stage).
    RK252A5 is quite large having an absolute V magnitude of 4.7 +/- 0.2 
    (brightness at a range of 1000 km and 90 deg phase angle). Its reflectance 
    spectrum is remarkably similar to TiO2 paint aged in the space environment. 
    Orbital calculations show it passed close to the Earth in 1975 but that it 
    appears to have originated from here during the early 60's.  After almost 50 
    years in space its visible reflectivity looks to have declined significantly 
    so its absolute magnitude when 'new' may have been close to 4.0.  Bill Gray 
    has also been able to determine a value of the area/mass ratio of about 
    0.008-0.009 m2/kg for the object through the influence of solar radiation 
    pressure on its orbit.  Its orbit also looks to be incompatible with 
    launches aimed at Venus or Mars.
    The best estimate of its nature is that it is associated with the failed 
    attempt to land Luna-4 (Lunik-IV) on the Moon.  The craft comprising the 
    Luna-4 probe mounted on a KTDU module (used to decelerate the probe before 
    landing) may be too small and have too low an area/mass ratio to fit the 
    observations.  However, the 4th stage of the Molniya 8K78/E6 launch vehicle 
    does appear to be a real possibility since its weighed 1150 kg empty and was 
    about 2.7 m in diameter and about 3 m in length, which equates to an 
    area/mass ratio of about 0.0077 m2/kg
    My question is: Does anyone have information on the fate of the 4th stage 
    used to launch Luna-4 towards the Moon?  Thanks in advance.
    Richard Miles
    British Astronomical Association
    Seesat-l mailing list

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