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I'm sure almost everyone on this site has seen the Artemis Map released by NASA. But I find it confusing attempting to interpret the flight path Artemis I will take. The mission is 25 days, and the Moon will have completed most of its orbit around the Earth in that time, but the map shows no motion of the moon. The animation on Wikipedia (screenshot below) shows this motion and the flight path in a much clearer (to me) way.

So my question is, is there an accurate way to interpret the flight path on NASA's Map, or is this mostly artistic licensing? Or was there just not an attempt to accurately show the flight path on this map?

My best guess is that it's the path in the lunar coordinate frame, but viewed from a distance, but then I'm not sure the trajectories around Earth make sense in that frame.

EDIT: I found an amination where the reference frame rotates with the Moon's motion (same page as the other animation). The trajectory near the moon seems similar to that in NASA's map, but not the return and ascent paths. I also generated my own path using JPL Horizons data in the non-rotating lunar reference frame (last image).

Nasa Map NASA Map

Flight path from above

Wikipedia Artemis flight map

Rotating with Moon

Moon Rotated

Moon reference frame enter image description here

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The NASA illustration is conceptual. Scale is distorted to show details of Earth and Moon. It uses a rotating frame of reference, so the diagram does not show the Moon's motion.

Artemis's trajectory in an inertial frame of reference ( the "flight path from above" screens shot) is counterintuative since it is illustrating a 3 body problem.

The Moon's gravitational sphere of influence is about 17% of its orbital radius. Artemis actually exceeds this in its distant retrograde orbit (DRO), so the DRO doesn't follow a Keplerian elipse. For this reason, a patched conic approximation has limited usefulness.

As well, there are 2 planned burns (days 16 and 20) during the DRO.

All very complicated! I suggest using the NASA illustration for conceptualization, then look at the Wikipedia animations. If you look at the DRO as a patched conic, it almost makes sense

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  • $\begingroup$ I'm not really looking for an intuitive explanation of the path. More of how you get the path in NASA's map from one of the other three paths I posted. $\endgroup$ Nov 18, 2022 at 0:37
  • $\begingroup$ @GregMiller ... the "rotating with the moon" freeze frame is the closest to the NASA drawing is there a particular discrepancy you see? $\endgroup$
    – Woody
    Nov 18, 2022 at 1:09
  • $\begingroup$ Yea, I noted that in my question too. Also noted the ascent and return trajectories don't match any of the 3, e.g. they don't cross (at least not far from Earth). If it's just artistic license, you'd think they would have noted that somewhere like they do in other artistic renderings, so a reference would be nice. But the fact that the two lobes near the moon match image #2 shows they tried to make it meaningful, so that makes me wonder if there's an explanation for the rest of the path that doesn't match. $\endgroup$ Nov 18, 2022 at 4:48
  • $\begingroup$ There's also a similar curve to the ascent and return paths in the Artemis logo. But they look nothing like that in any of the three reference frame images. $\endgroup$ Nov 18, 2022 at 4:51

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