RainCube one year after completing its mission: what we have learned and what lies ahead

RainCube one year after completing its mission: what we have learned and what lies ahead.

Simone Tanelli¹, Shivani Joshi¹, Ousmane Sy¹, Gian Franco Sacco¹, Robert Beauchamp¹, Nazilla Rouse¹, Eva Peral¹, Brad Ortloff¹, Douglas Price¹, Todd Mosher², Austin Williams², Chris Shaffer², Raquel Rodriguez-Monje¹, Ziad S. Haddad¹, Graeme Stephens¹, Eastwood Im­¹, Matthew Lebsock¹

1 - Jet Propulsion Laboratory, California Institute of Technology

4800 Oak Grove Dr., Pasadena, CA 91109; 818-354-1100

simone.tanelli@jpl.nasa.gov

2 - Tyvak Nano-Satellite Systems, Inc.

15265 Alton Parkway, Suite 200, Irvine, CA 92618; 949-753-1020

austin@tyvak.com

RainCube (Radar in a CubeSat) is a technology demonstration mission to enable Ka-band precipitation radar technologies on a low-cost, quick-turnaround platform. The RainCube instrument concept was conceived at the Jet Propulsion Laboratory in 2012 with the goal to demonstrate two key technologies in the space environment – 1) a miniaturized Ka-band precipitation profiling radar that occupies ~3U and 2) a 0.5m Ka-band deployable parabolic antenna that stows within 1.5U. In 2015, RainCube was selected within NASA Science Mission Directorate’s Research Opportunities in Space and Earth Science 2015 In-Space Validation of Earth Science Technologies. The spacecraft bus was developed by Tyvak Nanosatellite Systems, Inc., responsible for integration and test of the flight system and for mission operations. RainCube was delivered on time for its scheduled launch in May 2018 as part of ELana-23 from Wallops Flight Facility. It deployed from the ISS in July 2018, and completed its primary demonstration mission in September 2018. At the time of writing, the mission has received three extensions and is authorized to continue operating until August, 2020 provided that it maintains functionality.

The RainCube technology demonstration was envisioned and implemented with the aggressive objective of achieving its primary goals no later than 2018, in order to provide a timely and tangible proof of the validity of its innovative approach to the study teams formulating new approaches and mission concepts that address a number of scientific and operational objectives pertaining clouds convection and precipitation directly or indirectly informed by the findings and recommendations of the 2017 Decadal Survey produced by the National Academy of Sciences for NASA. As such, a number of challenges had to be addressed keeping not only the technical difficulties in mind, but also the timeliness of the outcome. After one year in orbit, RainCube has provided concrete proof of innovative approaches, confirmation of predicted radar performance, opportunity to develop and prove approaches to detect and mitigate issues, lessons learned and critical experiences in the assessment of risk, viability of parts, algorithm development and system architecture. In this presentation we will discuss a few of these topics, and articulate how they have affected the path forward in the definition of future observing system concepts, in the advancement of critical technologies, and in the refinement of science objectives and operational needs that can be addressed by small satellite missions in the near future.