Observation 4908250: CuPID (99511) TLE source changed - orbit do not make sense

Regarding Observation 4908250

It looks like the source for the TLE for CuPID changed from space-track.org recently. CuPID being 99115 (SatNOGS) and 49264 (space-track/celestrak etc).

The inclination of CuPID has changed (!!) from that of a polar orbit of 97.6 degrees like these from a couple days ago:

2021-10-23 16:21:01
Screenshot 2021-10-25 at 10-29-12 SatNOGS Network - Observation 4896283
Screenshot 2021-10-25 at 10-28-35 SatNOGS Network - Observation 4896284

Screenshot 2021-10-25 at 10-34-21 SatNOGS Network - Observation 4896283

to that of more a low-earth circular orbit with an inclination of 51.6 degrees from Celestrak for NORAD ID 49264

Screenshot 2021-10-25 at 10-19-43 SatNOGS Network - Observation 4908250

Screenshot 2021-10-25 at 10-21-38 SatNOGS Network - Observation 4908250
a completely different orbital profile.

What’s happened???


@satcolintel5 I went to the Celestrak page and it looks like the inclination is messed up on their page as well. Sounds like SatNOGS is reading the TLE correct, and Celestrak got it wrong!



The TLE looks correct now

Screenshot 2021-10-25 at 16-12-01 SatNOGS Network - Observation 4912271

Thanks to the SatNOGS team for fixing this! I’ve deleted my future CuPID observations and rescheduled them with the new (correct) TLE set.

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Actually that was done automatically, thanks for noting however, this is good to know and have it in mind.

By the way, future observations are updated with the latest TLE sets every 30min, so no need to re-schedule if the observation is after 30min, except if the TLE set has changed a lot, like for example near a satellite deployment.

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Thanks for this, that is good to know going forward. I’ve been hesitant to schedule important observations 48 hours out in case the TLE set used at the time of scheduling are updated closer to the actual observation time.

Just have in mind that, except for special cases*, TLE changes for LEO satellites are not that significant, and by that I mean you can use the TLE set for a couple of days without a serious issue. So, it is safe to schedule 48h hours in the future, even if the automation doesn’t work.

*Here are some of the special cases:

  1. TLE Change due to propulsion for avoiding collisions or for correcting orbit, for example ISS
  2. Use of preliminary TLE sets for newly deployed satellites that are updated in the first hours/days after deployment
  3. TLE for satellite near to re-entry