Phobos-Soil Project seeks observations of engine burns from South America

From: Ted Molczan (ssl3molcz@rogers.com)
Date: Wed Nov 02 2011 - 14:12:34 UTC

  • Next message: Denis Denisenko: "Re: observations of Phobos-Soil (Fregat) engine burns"

    Russia's Phobos sample-return mission, called Phobos-Soil (Phobos-Grunt in Russian), is scheduled for launch on 2011 Nov
    08 at 20:16:03 UTC, from Baikonur. 
    
    The Phobos-Soil Project has requested precise positional observations of the spacecraft during the two engine burns that
    will propel it out of its LEO parking orbit and send it to Mars, which will occur out of range of Russia's tracking
    network. 
    
    The request appears on the project's website, which explains the need for the observations, provides trajectory data
    (including TLEs), and invites prospective observers to register, so that they may report their observations:
    
    http://phobos.cosmos.ru/index.php?id=559&L=2
    
    The Ballistics page of the above site includes ground track plots that reveal the opportunity for observers in South
    America who are sufficiently close to the track, to observe a significant portion of the burns.
    
    There are challenges for prospective observers:
    
    - the spacecraft will be in eclipse (Earth's shadow) for nearly the entire portion of both burns visible from land.
    Fortunately, the exhaust plume is expected to be sufficiently bright to be observed from the ground.
    
    - the observational data is required in near-real-time (in other words: ASAP, immediately would not be too soon!)
    
    - the spacecraft will be at a low altitude, which greatly restricts the radius of visibility
    
    - the angular velocity at closest approach will be high for observers near the track
    
    The purpose of my post is two-fold. First, I am following-up and amplifying the heads-up that Richard Miles posted here
    last week, to help get the word out. Another SeeSat-L subscriber, Carlos Bella, who is in Brazil and close to the track
    of burn #1, has registered to observe and is alerting other observers and groups that he knows.
    
    Below are the ground track plots of both burns. The thin ground track line means normal flight; the heavy ground track
    line means engine is firing, which is of primary interest. The green lines to either side of the ground track are limits
    of visibility.
    
    If you are located between the green lines, near the portion of the track when the engine will be firing, then you may
    be able to observe. Perhaps you know someone else who could observe?
    
    http://phobos.cosmos.ru/uploads/pics/1eb_04.jpg
    
    http://phobos.cosmos.ru/uploads/pics/2eb_01.jpg
    
    Second, as time permits, I am making myself available to assist those who may have the necessary optical equipment and
    astronomical knowledge, but who may not be experienced with satellite orbits, TLEs (2-line orbital elements), or
    astrometry.
    
    Later today, I will follow up with some tips on observing strategy, but I can also assist by generating custom
    ephemerides (look-angles), and perhaps data-reduction. If many observers come forward and seek help, I may not be able
    to assist everyone, but I am confident that other list-members with as good or better skills will want to help out.
    
    Unfortunately, time is running short, so we need to get organized quickly.
    
    Ted Molczan
    
    
    _______________________________________________
    Seesat-l mailing list
    http://mailman.satobs.org/mailman/listinfo/seesat-l
    



    This archive was generated by hypermail 2b29 : Wed Nov 02 2011 - 14:13:11 UTC