Hi Bill

Hope you and your wife are getting some sleep
and now more experienced in dealing with the
new arrival!

I have a query about the prediction algorithm used
for artificial satellites. The original SGP4 and SDP4
routines use only the BStar term if my memory is
correct, so if BSTAR is zero then its treated as such.

As you may know a lot of the data NOT coming from
SPACETRACK does not have BStar values and
instead we use the drag term which is after the epoch
term in the 2/3 line element sets.

This seems to cause a problem in GUIDE- for example
with the current NROL-22 mission I have elements
which I plan to use for optical acquisition and when I
run the element set GUIDE gives predictions which are not
correct because BSTAR is zero. Running the elements in
other programs which use the drag term I get optical
visibility which is what Ive been advised by radio and
optical observers well to my north .

Is it possible for your program to use the drag term if
BSTAR is zero ? Ive had this problem with other
satellites in GUIDE where BSTAR is zero. Otherwise
I consider GUIDE the only program to use when doing
my optical positional determinations!

Wish your DOS version of GUIDE handled satellite
predictions - then I could use it to drive my Mel Bartel
set-up :-))

Many thanks
Greg