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getGroundTracks returning strange values randomly; sometimes tracks equal each other or are completely wrong #20
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Again after more investigation I believe this is something to do with inclination in orbits - perhaps some trig or division going wrong? |
More investigation - this error may not be happening when getting a single orbit track from |
Thanks for the heads up, I'll take a look when I can. The underlying SGP4 library satellite.js definitely has problems with some types of TLEs. If possible, could you share the TLE and some input times that reproduce this error? |
@davidcalhoun AII-BRAVO PROXIMA 2 IRIDIUM 100 Timestamps (using Date().getTime())
(AII-BRAVO never experienced an error) |
Thank you for the details, this helps a lot! Will investigate when I get a chance. |
Thank you again, the extra info was super helpful to track this down. This is now fixed in 4.2.12 |
Say I use the following code to get a ground track and print the result:
Sometimes, the results will make sense in that each array has different values, like this:
And the satellite's current position (using
getLatLngObj()
) on a map will lie on ground track [1].But quite often, for no discernible reason (after refreshing or whatever), some of the arrays will be equal to each other.
And the satellite's position will no longer lie on the plotted line for that orbit!
And sometimes, the values will be completely off everywhere:
Changing the
startTimeMS
does not fix this; nor does changing the TLE, or changingstepMS
. I have a hunch that this may be due to something with inclined orbits (TLEs with higher inclinations having more problems) but I have no real way to confirm this because I can't replicate the conditions that explicitly cause it to happen.The text was updated successfully, but these errors were encountered: