On 5/11/16, Jason Rearick jbr13@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.
<snip>
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 visible.
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.
73s
Bernhard VA6BMJ @ DO33FL