Re: [amsat-bb] Nasa keeps shuttle launch time secret

["Vince Fiscus, KB7ADL" <vlfiscus@xxxxxxx>]

At 12:23 AM 4/6/02 +0200, Udo Schneider <uschndr@zedat.fu-berlin.de> wrote:
>Hello Vince,
>
>How do you determine the "coplanar time" with IT?
>I don't see the trace of the "orbital plane" of ISS at the surface of the
>earth. The trace of the subsatellites points is another thing.
>I have Nova for Windows and STSPLUS too.
>
>Do you know the coordinates of the launch site?

28.5 N 80.5 W

My method is slow and there are probably better ways to do it.  Use the 
'IT' text tracking screen for the ISS and the XYZ coordinate display.  Use 
the coordinates of KSC as the observer.  Use the best ISS keps you can get. 
The closer to launch day the better.  Fast forward the ISS to the first 
closest north bound EQX to KSC on launch day. Fast forward the ISS a little 
more until its SSP is 28.5 N.  At this point the ISS should be east of 
KSC.  Record the X and Y coordinates and compute the angle arctan(y/x). 
Fast forward a little more until the arctan(y/x) of the observer is the 
same angle. At this point, the time on the 'IT' tracking screen should be 
close to launch time. You may need/want to use some Trig on the arctan(y/x) 
to make the angle more meaningful.

Another method I haven't tried, but should work.  Fast forward the ISS 
until it is 28.5 N latitude on launch day and east of KSC. Record the ISS 
longitude and time. Subtract the ISS longitude from the KSC longitude of 
80.5. The earth rotates about 15 degrees per hour.  Figure out the amount 
of time it takes the earth to the difference between the two longitudes and 
add that time to the ISS time recorded before.

Neither of these methods takes into account ISS orbital precession so you 
could figure that in to be more precise.

KB7ADL

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