[aprssig] ISS Tracking & Pass Information

[Lynn W. Deffenbaugh (Mr)]

On 10/13/2011 11:45 PM, Steve Noskowicz wrote:
>
> AOS: xx:yyz+aa:bbc - If you are not in a pass
> Pretty cool!  More stuff for my Beginner Guide.
>
>    RE xx:yyz
> 1-  Is this hh:mmZ  the delta time *to* the next AOS?   Why the "z"?  Just an identifier?

If you had actually sent a message, you'd have seen that the z was an 
unfortunate choice of placeholder.  All times are presented as deltas 
from now in one of the following forms:

1:25h - Means 1 hour 25 minutes (hourly presentation)
45:24m - Means 45 minutes 24 seconds (minutes presentation)
30s - Means 30 seconds (obvious)

> 2-  Is it rounded to the nearest minute, or is it the minute before AOS?

As you can see above, if it's less than an hour, it will show minutes 
and seconds "m", and if it's less than a minute, it will just show 
seconds "s".

>    RE +aa:bbc
> 3-  Is this duration in minutes:seconds?  If so, then what is "c" for?

Duration follows the same delta time formatter described above.  It may 
be hours, minutes, or seconds as appropriate to convey the scale of the 
number being presented.  Not that I've ever actually SEEN an hour-long 
pass, but RS-15's next pass over my QTH is +30:04m or just over 1/2 hour 
long, so I'm thinking it's theoretically possible.  Of course, for all I 
know about the real satellites, RS-15 might not even be UP there, but 
the TLE comes down from Celestrak, so it gets forecasted.

> > From the how-about-it department...
>    RE: .but for any of the other satellites found in the TLE...
>> set from http://www.celestrak.com/NORAD/elements/amateur.txt ...
>> If you have any trouble figuring out which satellite name...
>    Would it be possible to have a place to send a message to that returns all the currently tracked sat names?   e.g send a message to "SatPass" and get a reply (or replies) with list(s) of sat names that will return pass info...or is the list too long? (I'm not familiar with this "TLE" thing)

If you had hit the URL above, you'd know how many satellites are being 
tracked from that single TLE source.  I'm still trying to figure out a 
reasonable way to communicate this information via APRS.

Lynn (D) - KJ4ERJ - Author of APRSISCE for Windows Mobile and Win32