The overall objectives are as follow:

-Confirm the functionalities of the micro-organisms previously selected and study their respective biological performances (i.e. urea hydrolysis, ammonium oxidation and nitrite oxidation) as well as the process performances (i.e. urine nitrification)

-Consolidate and update the plans and protocols for the proposed post-flight analyses

-Confirm the feasibility of the end-to-end experiment scientific protocol by test in representative test set-up(s)

-Consolidate the scientific needs and associated scientific functional and performance requirements as well as the hardware requirements