What is this structure near NGC 2477 and NGC 2451 in Puppis? If you flip between the star and starless versions you can see it looks like an inverted U or upside down horseshoe. Its almost like a smoke ring or pressure tube - does anyone know what it is pls?
https://cdn.astrobin.com/thumbs/zBVdJeuW76Xy_1824x0__sPnTECk.png?v=1773073285
https://app.astrobin.com/i/a6ygfl if easier to see it by doing a mouseover
(Sorry its NGC 2451 not NGC 2546 but I don’t know how to change the title)