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After looking at this plot and many others I've come to the conclusion that this plot does not represent current JWST halo orbit. If the plot is supposed to be of JWST halo... it disagrees with many others.

enter image description here

In almost anything current I've seen the JWST approaches L2 coming up from "south", enters halo in +Z and and halo orbit is clockwise when viewed looking towards earth/sun. this plot shows exact opposite. Also notice view C) labels +Z axis but z values are negative there.

I suspect someone used "first angle projection" drafting practice and swapped Z axis +/-. First angle projection was used mainly in Europe and third angle projection was used everywhere else. (First angle projection engineering drawings were really screwy to read and easy to mess up with (lead to errors of interpretation). Everything was bassakwards)

This plot would agree with other information if view C) were moved to left of view A) and swapped Z +/-. Also view B) would move to above A) and swapped Z +/-.

Another way to correct would be to just mirror the trajectory tracks in B) an C) while leaving axis values as is (except must move C) label +Z RLP to proper side).

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    $\begingroup$ I am new to this. Can someone educate me on how to get graphic to appear in my question? the graphic shows well in other locations here. $\endgroup$
    – BradV
    Commented Jan 24, 2022 at 6:19
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    $\begingroup$ just figured it out.... $\endgroup$
    – BradV
    Commented Jan 24, 2022 at 6:26
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    $\begingroup$ @RogerWood The time of launch is no hint - the plot is just an example and very likely published in 2017, way before the final launch date was fixed. $\endgroup$
    – asdfex
    Commented Jan 25, 2022 at 9:25
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    $\begingroup$ Well... regardless... I insist on proving myself RIGHT!!! (intense self deprecating humor intended). I believe quite a few of what we see online are are honest efforts to calculate, predict and plan for JWST. However... many are merely graphics thrown together by nontechnical people who just want to show generalities and don't need or want to be fully correct. Too much NASA stuff seems to fall into this category. $\endgroup$
    – BradV
    Commented Jan 25, 2022 at 20:57
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    $\begingroup$ The link may have been posted already, but the graphic comes from the Space Telescope Science Institute: jwst-docs.stsci.edu/jwst-observatory-characteristics/jwst-orbit quote: "A representative example of a valid JWST trajectory and orbit. Panel a is the view of the orbit projected onto the ecliptic plane; panel b is the view in the ecliptic plane, and panel c is the view along the Earth-Sun line." 30 May 2017, hth $\endgroup$
    – blobbymcblobby
    Commented Jan 26, 2022 at 0:40

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No, plot is not screwed up.

after discussion here and other locations and I now realize that the plots are sound and correct with the only 'problem' being that the +Z label on plot C) is in the wrong location.

Sorry for the 'should have known better' question.

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    $\begingroup$ That +z label really screwed my thinking too. $\endgroup$
    – Roger Wood
    Commented Jan 28, 2022 at 21:23

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