I've read in various places that Mariner 9 was supposed to remain in orbit until sometime in the 2020s or 2030s. However, I've never seen an authoritative quote for the exact end of its mission. (One may not exist, of course.) The wikipedia page gives a date of 2022, with a footnote, but unfortunately the link (to a NASA page) is dead.
Does anyone know anything more? Also, would it be theoretically possible to image Mariner 9 (assuming we knew where it was) using any of the other orbiters?
Doug M.