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RE: Preferred Phase 3 Orbits



> Unless you put the spacecraft in an orbit with a pretty high 
> perigee, it
> becomes inaccessible to each hemisphere as it nears perigee.  If the
> subsatellite point is at 0 degrees lattitude and the 
> spacecraft is at a
> low perigee, it is below the horizon for pretty much everyone 
> outside of
> the equitorial belt.

Agreed.  Need at least a few '000 km perigee height to be reasonably useful
at perigee.  Anyone tracking AO-40 will see that.

> If perigee occurs somewhere over the atlantic or pacific ocean, the
> spacecraft becomes pretty much totally inaccessible for a 
> period of time.

True, but another argument (pardon the pun!) with regards to perigee in this
part of the world is that below a certain altitude (which is somewhat above
4000km), all we VK's get to talk to is ourselves, ZL and a few Asian
countries, especially if the SSP is to the south (I'm pretty sure the
penguins in Antarctica couldn't gove two hoots about satellite comms ;) ).

I did do some pass predictions using the simulated Keps that were on the
AMSAT-NA page for the final orbit, and noted that there were excellent pass
opportunities for VK/USA (excellent!), VK-Japan/Asia, reasonable openings to
Africa (a few hours), but Europe was fairly limited.  Total visibility was
in the order of 16 hours/48, most of it favouring the USA and Japan.

The current orbit gives much better access to Europe from this side of the
world.  That's probably the most obvious difference, and obviously, the
percentage of time the satellite is visible is vastly improved as well.

Just a few observations from 37S :)
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