RE: Decay watch: 2001 Feb 21

From: Matson, Robert (ROBERT.D.MATSON@saic.com)
Date: Wed Feb 21 2001 - 14:32:01 PST

  • Next message: Dave Kerr: "Digital Photography of Satellites"

    > For So Cal, I see a pass near decay time at about 18:24 PST +/- a few
    > min. From Tustin it'll be about 40 deg high in the ESE.
    
    Hi Mark,
    
    Based on the latest SATEVO elements from Alan, it doesn't look
    very promising for southern California.  The elevation is likely
    to be quite a bit lower than 40 degrees.  Using the 3rd elset
    in Alan's latest list of four sets, the culmination is only
    13 degrees for Tustin at around 18:13 PST.  If you use the
    fourth SATEVO-generated elset (closest to the time of our
    pass), the elevation is less than 7 degrees.  Of course, Alan's
    progression assumes reentry on an earlier orbit, so it's probably
    inappropriate to even consider the 3rd or 4th TLE.  Hopefully
    someone will spot it on the rev before and give us a report.
    
    As a reminder, do not use SGP4 when propagating decaying
    Molniyas with Alan Pickup's elsets -- SGP4 grossly overestimates
    the satellite altitude.  SGP and HANDE should give reasonable
    consistent results.
    
    Best,
    Rob
    
    -----------------------------------------------------------------
    Unsubscribe from SeeSat-L by sending a message with 'unsubscribe'
    in the SUBJECT to SeeSat-L-request@lists.satellite.eu.org
    http://www2.satellite.eu.org/seesat/seesatindex.html
    



    This archive was generated by hypermail 2b29 : Wed Feb 21 2001 - 14:31:59 PST