Elektron debris

From: George Olshevsky (george.olshevsky@gmail.com)
Date: Sat Feb 25 2006 - 03:57:51 EST

  • Next message: Greg Roberts: "Obs 23 feb 2006"

    I've now gotten into the year 1964 of updating and revising my
    "Chronological Summary Log of Orbited Objects," that is, to identify
    as best I can every object in the SATCAT and list its initial/earliest
    known orbital elements, which are not directly available in any one
    table (that I can find). In particular, I'm aiming to purge my version
    of the Space Track list of the word "debris," which is simply not
    specific enough for me. There's a lot of guesswork in the project but
    as I've said before, it's fun and it keeps me out of the bars in the
    evenings, which my wife appreciates.
    
    In a few days I'll be able to send a review PDF for the years
    1957-1963 to anyone who requests it. Unfortunately, there's Space
    Track information in it, so I can only send it to registered Space
    Track users. The good news is that that probably includes everyone on
    the SeeSat list(!). Once I finish 1964, I'll add it to the PDF and
    make the longer table available. And so on, right to the present,
    which I hope to reach in time for the 50th anniversary of Sputnik 1,
    around October 4, 2007. Tabulating one year's launches comprises about
    2 weeks spare-time work, more if there are lots of fragments for a
    year (e.g., 1961). One really begins to appreciate Leo Barhorst's work
    on the RAE table and Jonathan McDowell's compilations after spending
    time on a similar project!
    
    I have tried to identify the debris associated with Elektrons 1 and 2,
    launched by the USSR January 30, 1964. The objects for this launch
    have ID numbers 1964-006A through AF. Remarkably, this moderately long
    list of debris is not the result of an on-orbit breakup [well, not
    >all< of it: one piece is: 1964-006AF, the last in the series, which
    is the one and only catalogued fragment from the aerodynamic breakup
    of the Vostok 8K72K Blok E second stage--1964-006D--which occurred
    February 13, 1998 and resulted in numerous orbited objects (is there
    any kind of count of these?), most of which quickly decayed before
    they could be catalogued and their elements could be determined]. This
    corrects the notation in the RAE table, which states that objects E-AF
    are the result of this breakup. This is impossible, since pieces E-AE
    were catalogued and many decayed well before February 13, 1998(!). AF
    remained in orbit until July 11, 1998; D came down February 15, 1998,
    two days after the breakup.
    
    So what, then, are those objects E-AE? Well, Space Track identifies
    them all as Elektron 1 debris--except for AF, which it correctly (as
    far as it goes) identifies as debris from the second stage. (By the
    way, I've numbered the USSR/CIS rocket stages as stage 0 for any
    boosters that fall away while the core stage--stage 1--is still
    burning, and the stages after the core as 2, 3, etc. This is
    consistent with the way stages are numbered for other countries but
    not always consistent with the way USSR/CIS rocket stages are numbered
    in many sources.) But initial/earliest known orbital elements for
    objects N, V, and AE are way too high for them to have broken free of
    Elektron 1. Those three at least must be Elektron 2 debris. There is
    also the possibility that debris from Elektrons 3 and 4, launched
    later in 1964 into similar orbits, has been catalogued as Elektron 1
    debris. Alas, there seems to be no way to further distinguish such
    objects in this debris cloud.
    
    Almost all the objects E-AE have small RCS and orbits that change
    rapidly, indicating they're lightweight pieces strongly subject to
    atmospheric and solar forces. The visual appearance of Elektrons 1 and
    2 suggests these objects are individual or small groups of solar cells
    that over the years have become detached from the parent satellites
    (micrometeoroid strikes or deterioration of adhesive?). Elektron 2
    displays a larger solar-cell-covered surface area than Elektron 1, so
    it is likely that more than just three of the objects came off
    Elektron 2, but this would be difficult to ascertain without actually
    seeing the satellites themselves as they appear today. One object, P,
    has a larger RCS that suggests it may be a whole paddle of cells that
    has broken off Elektron 1 (Elektron 2 doesn't have solar cell paddles,
    but it does have an apron of solar cell panels).
    
    The other objects are more mundane. A and B are Elektron 1 and 2
    respectively, and D is the second stage (RAE calls it the third stage)
    before it broke up. C is some kind of SYLDA-like adapter by which
    Elektron 1 was held during the launch and which followed it into
    roughly the same lower orbit when the satellite detached. According to
    what I've read, Elektron 1 detached while the second stage was still
    burning, to enter a much lower orbit than its partner Elektron 2. The
    Elektrons' mission was to investigate the lower and upper van Allen
    belts in tandem. I'd like to know more about the adapter. Did it have
    a motor of its own? And how were Elektrons 1 and 2 configured inside
    the rocket before launch? Elektron 1 must have been positioned above 2
    in the nose of the rocket, so the adapter would have had to have some
    kind of fancy pyrotechnic to get itself and Elektron 1 off the rocket
    while it was still burning, unless there was a restart.
    
    Elektrons 1-4 seem to have been the final spacecraft launched with the
    Vostok 8K72K rocket, which had previously carried Vostoks 1-6 and
    other Sputniks into orbit. Thereafter, the 8K72K was phased out and
    replaced by newer versions of the Vostok rocket. The Elektron missions
    are described in the TRW Space Log and at a number of different
    Internet websites.
    
    Any further information on these launches, such as other opinions on
    the nature of the debris, would, of course, be greatly appreciated!
    
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