[amsat-bb] Satellite timing question.

B J va6bmj at gmail.com
Wed May 11 04:14:59 UTC 2016

On 5/11/16, Jason Rearick <jbr13 at md.metrocast.net> wrote:
> Yes, I have and use Gpredict, but don't know how far ahead to go to find
> when the birds come back around to about the same times as they did last
> month.  I figure they are on a cycle that repeats every so many days, weeks,
> or months.


Keep in mind that Gpredict will only produce data for up to 50 orbits
in the future.

Each day, I put the AOS times for the satellites I track into my
computer's calendar program.  Before I do that, I print out those 50
orbits as text files and import them into a database.  I can then
check the dates or specific times that a certain satellite will be

A simple way would be to estimate the precession rate from that
orbital data and do a back of the envelope calculation for when a bird
will be in a favourable position.

Of course, one could always resort to looking up the necessary
equations in an orbital mechanics text and do some number-crunching.


Bernhard VA6BMJ @ DO33FL

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