RE: [Nova-Net] Apollo TLE to Keplarian elements

From: Dale Ireland (direland@drdale.com)
Date: Tue May 25 2004 - 19:49:58 EDT

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    Sorry, I quoted elements for object 601 instead of 6001. Unfortunately 6001
    (the Saturn booster) isn't included in the elements archive on Jonathan's
    site.
    Dale
    
    -----Original Message-----
    From: Ken Ernandes [mailto:n2wwd@mindspring.com] 
    
    
    Dale -
    
    The Keplerian elements listed could not be the Apollo 16 trans-lunar
    trajectory.  For starters, you have a nearly 70-deg inclination angle
    (69.8619-deg) and represent a somewhat circular (ecc = 0.0483667),
    low-altitude orbit (n = 15.21267116 rev/day).  Furthermore, the epoch of
    these elements is 23 June 1963 23:29:33.389 (63174.97885867).
    
    In order to have a trans-lunar trajectory with respect to the Earth (an
    implicit assumption for a TLE) the ecc would need to be greater than 1.0 and
    the mean motion would necessarily be negative (i.e., an hyperbolic
    trajectory).
    
    IMHO, your best bet would be to put in a special request to NASA for an
    Earth-Centered Inertial (ECI) position and velocity state vector (with epoch
    included) for the trajectory.  This would be convertible to a Heliocentric
    trajectory.  Considering there is the possibility of reviving Manned Moon
    and even Mars landing missions, NASA might just take the trouble to dig them
    out of the archives.
    
    73, Ken N2WWD
    
    
    
    -----Original Message-----
    From: Nova-net-bounces@nlsa.com [mailto:Nova-net-bounces@nlsa.com]On
    Behalf Of Dale Ireland
    Sent: Tuesday, May 25, 2004 10:00 AM
    To: Nova List (Nova List)
    Cc: SeeSat-L
    Subject: [Nova-Net] Apollo TLE to Keplarian elements
    
    
    Hello
    I wanted to plot the position of the Apollo 16 Saturn IVB booster in
    trans-lunar trajectory (on the way to the Moon) in 1972.
    I obtained the two line elements, which I "believe" are the trans-lunar
    elements
    
    1 00601U          63174.97885867  .00885526                        27
    2 00601  69.8619 172.9878 0483667 138.6852 225.0868 15.21267116  1270
    
    Nova For Windows doesn't see these as valid elements. Probably because the
    satellite has escaped Earth orbit. How can I convert these two line elements
    into Sun centered Keplarian elements for use in other planetarium programs.
    Or is there a way to use them in NFW?
    
    Dale Ireland
    
    
    
    
    
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