> Anything that can return a sample. Notice that Curiosity collects samples, but omits the sample return rocket.
NASA (and also the Soviet Union and ESA) have repeatedly designed Mars sample return missions, but have not done them for budgetary reasons; it would be tremendously difficult and expensive.
Here's the current one: https://en.wikipedia.org/wiki/NASA-ESA_Mars_Sample_Return - however, given that it was hitting funding problems even _before_ ol' minihands gutted NASA funding, it seems destined to become yet another NASA/ESA canceled program (there's a bit of a history of ambitious NASA/ESA collaborations which die when one side or the other pulls the budgetary plug; JWST was likely lucky to escape this fate, say).
This puts it in a particularly weird place, as the earth return section is already built and due to launch on an Ariane 6 in two years (it will then proceed, slowly, to Mars using an ion drive, and await the lander and Mars launcher, which will presumably never arrive because budgets).
You're suggesting we can state "Mars has no life" based on a single sample?
If that's so, I can produce a sample of material from the center of the Amazon rain forest that will conclusively prove to you that Earth is also lifeless.
> A good enough microscope can easily tell the difference between life and non-life, especially in the presence of water.
They are still arguing over this one three decades later: https://en.wikipedia.org/wiki/Allan_Hills_84001
https://www.science.org/doi/10.1126/science.abg7905
" Inorganic precipitation processes are capable of producing a wide range of morphological outputs. This range includes shapes with both crystallographic and non-crystallographic symmetry elements. Among the latter, morphologies that mimic primitive living organisms are easily obtained under different physico-chemical conditions including those that are geochemically plausible. The application of this information to the problem of deciphering primitive life on the early Earth and Mars is discussed. It is concluded that morphology cannot be used unambiguously as a tool for primitive life detection. "
https://www.spiedigitallibrary.org/conference-proceedings-of...