Lunar Ice Cube: BIRCHES Payload and the Search for Volatiles with a First Generation Deep Space CubeSat

Lunar Ice Cube, a science requirements-driven deep space exploration 6U cubesat mission was selected for a NASA HEOMD NextSTEP slot on the EM1 launch. We are developing a compact broadband IR instrument for a high priority science application: understanding volatile origin, distribution, and ongoing processes in the inner solar system. JPL\u27s Lunar Flashlight, and Arizona State University\u27s LunaH-Map, both also EM1 lunar orbiters, will provide complimentary observations to be used in understanding volatile dynamics. The Lunar Ice Cube mission science focus, led by the JPL science PI, is on enabling broadband spectral determination of composition and distribution of volatiles in regoliths of the Moon and analogous bodies as a function of time of day, latitude, regolith age and composition and thus enabling understanding of current dynamics of volatile sources, sinks, and processes, with implications for evolutionary origin of volatiles. Lunar Ice Cube utilizes a versatile GSFC-developed payload: BIRCHES, Broadband InfraRed Compact, High-resolution Exploration Spectrometer, a miniaturized version of OVIRS on OSIRIS-REx. BIRCHES is a compact (1.5U, 2 kg, 7W including cryocooler) point spectrometer with a compact cryo-cooled HgCdTe focal plane array for broadband (1 to 4 micron) measurements, achieving sufficient SNR (\u3e400) and spectral resolution (10 nm) through the use of a Linear Variable Filter to characterize and distinguish important volatiles (water, H2S, NH3, CO2, CH4, OH, organics) and mineral bands. We are also developing compact instrument electronics which can be easily reconfigured to support the instrument in \u27imager\u27 mode, once the communication downlink band-width becomes available, and the H1RG family of focal plane arrays. Thermal design is critical for the instrument. The compact and efficient Ricor cryocooler is designed to maintain the detector temperature below 120K. In order to maintain the optical system below 220K, a special radiator is dedicated to optics alone, in addition to a smaller radiator to maintain a nominal environment for spacecraft electronics. The Lunar Ice Cube team is led by Morehead State University, who will provide build, integrate and test the spacecraft, provide missions operations and ground communication. Propulsion is provided by the Busek Iodine ion propulsion (BIT-3) engine. Attitude Control will be provided by the Blue Canyon Technology XB1, which also includes a C&DH \u27bus\u27. C&DH will also be supported, redundantly, by the Proton 200k Lite and Honeywell DM microprocessor. Onboard communication will be provided by the Xband JPL Iris Radio and dual patch antennas. Ground communication will be provided by the DSN Xband network, particularly the Morehead State University 21-meter substation. Flight Dynamics support, including trajectory design, is provided by GSFC. Use of a micropropulsion system in a low energy trajectory will allow the spacecraft to achieve the science orbit within a year. The high inclination, equatorial periapsis orbit will allow coverage of overlapping swaths, with a 10 km along-track and cross-track foot-print, once every lunar cycle at up to six different times of day (from dawn to dusk) as the mission progresses during its nominal six month science mapping period

Radio-Frequency Interference (RFI) Mitigation for the Soil, Moisture Active/Passive (SMAP) Radiometer

The presence of anthropogenic RFI is expected to adversely impact soil moisture measurement by NASA s Soil Moisture Active Passive mission. The digital signal processing approach and preliminary design for detecting and mitigating this RFI is presented in this paper. This approach is largely based upon the work of Johnson and Ruf

Nature of and Lessons Learned from Lunar Ice Cube and the First Deep Space Cubesat 'Cluster'

Cubesats operating in deep space face challenges Earth-orbiting cubesats do not. 15 deep space cubesat 'prototypes' will be launched over the next two years including the two MarCO cubesats, the 2018 demonstration of dual communication system at Mars, and the 13 diverse cubesats being deployed from the SLS EM1 mission within the next two years. Three of the EM1 cubesat missions, including the first deep space cubesat 'cluster', will be lunar orbiters with remote sensing instruments for lunar surface/regolith measurements. These include: Lunar Ice Cube, with its 1-4 micron broadband IR spectrometer, BIRCHES, to determine volatile distribution as a function of time of day; Lunar Flashlight, to confirm the presence of surface ice at the lunar poles, utilizing an active source (laser), and looking for absorption features in the returning signal; and LunaH-Map to characterize ice at or below the surface at the poles with a compact neutron spectrometer. In addition, the BIRCHES instrument on Lunar Ice Cube will provide the first demonstration of a microcryocooler (AIM/IRIS) in deep space. Although not originally required to do so, all will be delivering science data to the Planetary Data System, the first formal archiving effort for cubesats. 4 of the 20 recently NASA-sponsored (PSDS3) study groups for deep space cubesat/smallsat mission concepts were lunar mission concepts, most involving 12U cubesats. NASA SIMPLEX 2/SALMON 3 AO will create ongoing opportunities for low-cost missions as 'rides' on government space program or private sector vehicles as these become available