SBG September 2020 Update
The Surface Biology and Geology Study Team had a busy summer in many ways, successfully wrapping up the Architecture Assessment Phase (Phase 2) and presenting the candidate architecture and two alternatives to the community on July 14th and to NASA Headquarters on July 29th. Despite the challenges from the COVID-19 pandemic, the SBG team continued the series of planned mission design labs at Langley, Ames, Goddard, and JPL, engaging with the research and applications community, and coordinating with Headquarters and potential international partners to remain on a fast-paced schedule.
The Third Community Webinar, on July 14th, 2020, presented in detail the ‘value framework’ for how meeting science objectives and mission cost (Phase A-E) featured in the appraisal of the ‘many-to-few’ architectures posed in Phase 1 and filtered during Phase 2. With high community interest, over 500 people registered and over 200 people joining the Webinar, where Program Scientist Woody Turner presented the goal of SBG, followed by Project Manager, Jamie Nastal (JPL), presenting an overview of Phase 1 and 2.
Dave Schimel (JPL) presented the science scoring methodology rated architectural candidates in terms of how well they met the measurement objectives for each of the science questions from the NASA Decadal Survey for spatial resolution, temporal revisit, spectral range, and signal to noise. Additional science value was given to those architectures that paired with international partnerships to increase revisit, or to provide coincidence between the visible-to-shortwave infrared (VSWIR) and thermal-infrared (TIR) observations. The role of international partnerships in providing launch vehicles, spacecraft, instruments, and calibration and validation opportunities was detailed by Chip Miller (JPL), emphasizing how constellations can provide revisit times that meet the Decadal Survey science and applications objectives. The costing and pairing of VSWIR and TIR architectural elements was presented by Dave Bearden (JPL) and Jon Chrone (LARC), which led to the descriptions of the recommended architecture and two alternatives.
The recommended architecture and two alternatives, as presented to NASA Headquarters on July 29th, 2020, aimed to meet the highest science objectives and fall within the cost constraint guidance of the Decadal Survey, while taking into account the existing Program of Record and leveraging international partnerships. The recommendation was for a two platform solution, a wide-swath VSWIR architecture with a morning overpass that would be similar to the planned European Space Agency CHIME spectrometer, and a TIR spacecraft with an afternoon overpass matching the proposed CNES/ISRO TRISHNA mission. The alternative architectures consisted of either a single spacecraft, which gained on coincidence whilst trading temporal revisit, and a second option of a VSWIR narrow-swath constellation and wide-swath TIR.
As NASA Headquarters evaluates the options, the SBG team is actively continuing webinar series for each of the Working Groups (Algorithms, Applications, Modeling, and Cal/Val), while planning Phase 3 and 4 (description of architecture) and establishing the project team to carry out activity for Mission Concept Review (planned for fall of 2021). Stay in touch with SBG via Twitter (@nasa_sbg) and by joining our Working Groups, or by attending our sessions at the American Geophysical Union 2020.