[X] My Assistant

[Doug M.]

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.

[nprev]

I'd actually be surprised if it is still in orbit. That 50-yr minimum estimate was made a long time before the dynamics of the martian atmosphere were well understood to say nothing of the detailed behavior of its upper portion. Plus it was, what, four solar cycles ago or so?

Tons of variables, but most of those would seem to act to decrease orbital longevity rather than prolong it. We'll never know, unfortunately.

[mcaplinger]

I'd actually be surprised if it is still in orbit. That 50-yr minimum estimate was made a long time before the dynamics of the martian atmosphere were well understood...

On the other hand periapsis was about 1600 km so it's not like it gets deep into the atmosphere.

There might be some insight in http://adsabs.harvard.edu/full/1974CeMec...9..395B but I haven't read it yet.