The Pod Bay

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Rafa

02:56

Hello and (late) Happy New Year to all! Would anybody familiar with numerical propagation of orbits be able to give me a quick rough estimate of how much and how quickly accurate propagation (with e.g. the HPOP in STK or OreKit) of satellites in LEO (e.g., the ISS) deviates from the real position?

The reason I'm asking is because I've been testing my own implementation of a high-precision propagator with the ISS, and get the following type of deviation for the X, Y and Z components of position (difference is in meters, time is in hours):

I thought this type of question would better fit here rather than as a proper full-fledged question in the main site, but apologies in advance if this was not the appropriate place!

7 hours later…

Rafa

09:34

As a follow up, the error seems to go almost completely away by using a drag force around 20% lower than what is specified in the OEM files distributed by NASA

And the error is corrected as well in all other components using the same reduced drag... any idea why the results would be so much more accurate using a drag different than that provided in the original ephemerides by NASA? (I'm using the OEM ephemerides freely available at spotthestation.nasa.gov/trajectory_data.cfm by the way)

I guess it might actually end up being worth to ask a full question :)

4 hours later…

Space Exploration Meta

14:08

Q: Inconsistencies in the practice of SE policy on this site

Please bear with me because I do not have a long experience with SE. During my short life here, it seems to me (I accept that I can be wrong) that there are several inconsistencies in the way you practice auto-moderation (which is a good policy, by the way). I will use just two examples to illust...

discussion

2 hours later…

Feeds

15:38

stackoverflow.blog/2022/01/12/…

1 hour later…

Space Exploration Meta

16:43

Q: 2021: a year in moderation

As we say goodbye to the old year and welcome the new one, we have a tradition of sharing moderation stats for the preceding calendar year. As most of you here are aware, sites on the Stack Exchange network are moderated somewhat differently to other sites on the web: We designed the Stack Exch...