I am contesting all mentions of the Nanairo sun sharing an orbit with Meido. The only evidence of this is the image and navigation system shown in Spec1, but I believe that that image is simply Meido's orbit, while the sun is stationary. I believe there is more evidence to this latter hypothesis:
1) There is no such orbit in the navigation system as it is shown in BtP. Notably, Meido is not displayed in this rendition either, as it is not in this game. This means removing Meido was enough justification to remove the orbital path from being displayed too, despite the sun still being there (and being promoted to a selectable area). If the sun had shared this orbital path, it could still have been present, instead of being hidden along with Meido.
2) The orbital path makes sense for Meido alone, being so far away that the pull of the sun's gravity would be extremely weak. It may seem that Meido is headed directly into the sun in this hypothesis, but it can also be inferred that Meido's orbital period is extremely large due to the weak pull; so much so that Meido itself is barely in motion. The evidence for this is that Meido has been "too far away" for the NPP to explore for as long as we know. If it were following the path at a reasonable speed, however, it would eventually come into more-than-reasonable proximity to the inner planets, but it has not done so. Therefore, it is a part of this hypothesis that Meido has such a low speed that the orbital path exists, but is hardly making progress. Additionally, it is understandable for planets with low enough speeds to eventually fall into their stars, meaning Meido is not even in a stable orbit, but in orbital decay. This could be evidenced by the extremely elliptic path it is shown to have, picking up speed as it nears the sun. However, this path would be a far-distant prediction, as Meido is again likely almost stationary where it is now.
To recap, I believe "Meido being almost stationary due to its distance, but being plotted to eventually collapse into the sun should it pick up speed" has more evidence than "Meido and the sun share an orbit", which would require some other entirely unknown source of gravity in the center of the system.
(Other edits I made include referring to the Nanairo Sun as such instead of a star, as it is explicitly called that in BtP, and thus makes sense in-universe)
Feel free to revert my edit and contest if anyone believes otherwise! There may be evidence I have missed.