csete / gpredict

Gpredict satellite tracking application
http://gpredict.oz9aec.net/
GNU General Public License v2.0
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Remove 50 pass/14 day limitation #178

Open whitis opened 4 years ago

whitis commented 4 years ago

Edit -> Preferences -> Predict -> Pass Conditions -> "Number of passes to predict" cannot be set higher than 50. This is an unreasonably low limit. The DEFAULT should be around 100 and you should be able to set it higher. For the ISS, 50 passes runs out of passes in 7 days or less, and you aren't sure if it finished the last day. Passes should occur within ___ days is limited to 14, which should also be higher.

You are now competing against web based services that usually allow 10 day predictions or more. That is actually a reason people fall back on the web based services instead of using a proper application that works when the internet is down. Heavens above, for example, does 10 day predictions but will then let you step forward 10 days and do more. The command line Predict will happily give out passes0 from now till january and beyond. n2yo will do 10 days. AMSAT suffers from the same 50 pass limitation but you can edit the HTML code for the select box and do 100.

Yes, if you go too far out the TLEs may not be accurate enough. But even then it can still be useful to know when good passes are likely to occur in the future for planning purposes and rerun the predictions at the time for more accuracy. Even weather underground does 10 days and that is for weather! Even without accuracy, it can help with determining how often good passes are likely to occur, looking at long term patterns (setting ground track to more than 10 passes would be useful here).

Partial workaround: update TLEs, use the Time Controller to teleport a week in advance and make sure Edit ->Preferences -> Predict -> Pass Conditions -> "Always use real time for pass predictions" is unchecked. But you aren't sure if the last day was complete, you have to splice reports together, and it wastes a lot of time.

Also, ground tracks should default to ON but there isn't even a setting for that like there is for skytracks. And skytracks should default to on. You are increasing the learning curve, unnecessarily with all the fiddling that needs to be done to make the app work as well as an online service. It should come configured as closely as possible to ready to run out of the box. I shouldn't have to give people five pages of configuration instructions so they can do what you can do in 3 minutes on a web site. Default view should be all views or 4 views (list view seems to be redundant as upcoming passes view shows the same and more). Once people have tried out the program, they can fiddle.

Versions: Gpredict 2.0-4 ubuntu package, OR Gpredict-2.2.1.glibc2.14-x86_64.AppImage Ubuntu 18.04.2 LTS