Cubesat Validation for New Spaceborne Atmospheric Observations

A host of new technologies relevant to sensing, calibration, and data exploitation are now coming online that have the potential to enable higher-performance observing systems (lower noise, finer resolution, broader coverage, etc.) that are also smaller and offer cost savings relative to conventional approaches. Laboratory prototyping and demonstration are the logical first steps in bringing these new technologies along a path to infusion in a flight mission, but it is often the case that some form of in-space validation is needed to prove out all relevant elements of a new observing system in an operational context. CubeSats and SmallSats, coupled with relatively low-cost launch options now available on rideshares, are facilitating this validation in multiple ways. Here we discuss two validation efforts for two NASA earth observing projects that are in two very different phases of mission implementation: TROPICS, an earth venture mission now in its operational phase, and CREWSR, an instrument prototyping project funded by the NASA Earth Science Technology Office (ESTO) Instrument Incubator Program (IIP). TROPICS was preceded by multiple in-space validation missions (most recently the Pathfinder mission), and CREWSR is now proceeding successfully along a path to be ready for a future in-space validation mission. In this paper, we provide some experiences, conclusions, and lessons learned from each of these two efforts along their project lifecycles.