Opportunities and value that small satellites offer for space weather research

Paul O’Brien

Space Sciences Department

The Aerospace Corporation

Second International Workshop on Small Satellites for Space Weather Research & Forecasting

Acknowledgements: C. Gabrielse, L. Blum, J. Lee, X. Li, and J. Carroll provided information on GTOsat/REMS, uCPT, REPtile, and LEMUR

© The Aerospace Corporation, 2022

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Outline

• Test new sensors
• Targeted re-flight of flagship science sensors
• In situ validation of simple sensors
• Rapid turnaround on critical needs
• Proliferation of sensors

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Test new sensors

• AC-6 Dos1 was a test flight for REACH Z dosimeter
• AC-6 two 0.5U cubesats
• REACH is a constellation of 32 dosimeter pairs on IridiumNEXT
• At the time REACH was conceived, a new class of dosimeter, for low energies, was only on the drawing board
• The AeroCube-6 mission flew and proved out these new dosimeters
• They were incorporated as the “Z” flavor of dosimeter on the REACH constellation (https://doi.org/10.5281/zenodo.5988170)
• Flight of uCPT on AC-10
• 7.6x4.8x4.1 cm
• 268 g
• Electrons 0.1-2.5 MeV
• Protons and ions 80 keV-1 MeV
• Raised TRL of compact environmental sensor

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Targeted re-flight

• SmallSats offer an opportunity to re-fly simplified/miniaturized proven sensors from flagship missions
• Increase chance to witness extreme events
• Get more science out of flagship mission investment
• Transition to space weather monitoring mission
• REPTile on CSSWE
• Based on REPT from Van Allen Probes
• Mission PI Xinlin Li
• LEO (~600 km, 65^o)
• 0.6-4 MeV electrons
• 1.25 kg sensor
• Launched 2012, operated until 2014, CIRBE follow-up in mid-2023
• REMS on GTOsat:
• Based on MagEIS from Van Allen Probes
• Mission PI Lauren Blum, REMS PI Christine Gabrielse, DPI Drew Turner
• GTO (~6 RE, < 50^o)
• 0.1-1 MeV electrons
• ~0.6-7 MeV protons
• 1 kg sensor
• Launch TBD, 1 year main mission

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In situ validation

• SmallSats can be used to calibrate simple sensors hosted on multiple vehicles: allow the smallsat orbit to drift among the vehicles hosting the sensors
• For example, AMPERE uses engineering magnetometers from Iridium satellites to estimate field-aligned currents
• One could fly a science magnetometer on a smallsat in a perturbed Iridium-like orbit to
• Visit each Iridium satellite and validate the interpretation of its engineering magnetometer
• Validate interpolated fields between satellites
• One could use the same approach to calibrate the REACH dosimeters or any other hosted sensor payloads

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• Key technology need: propulsion to get into wandering orbit

Calibration

Wanderer

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Rapid turnaround

• SmallSats typically have faster development cycles to launch, allowing them to more rapidly prove out new sensor technologies or approaches
• AeroCube-6 is a perfect example of this, as the REACH program was already underway when AC-6 launched
• The AC-6 low energy dosimeters had never been flown before, and the REACH program wanted flight data before committing to them
• The successful demonstration of low energy dosimeters on AC-6 allowed the REACH program to embrace the technology
• AC-6 launch was June 2014
• First REACH low energy dosimeter (flavor Z) was launched February 2017

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Proliferation of sensors

• For small-scale phenomena or phenomena requiring continuous monitoring, large constellations are required
• SmallSats enable proliferation of sensors throughout orbits of interest
• E.g., Spire Global LEMUR: 6kg, ~500 km orbit, >2 year lifetime, carries a GNSS-RO sensor

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Image Credit: NASA, �https://www.nasa.gov/feature/esnt/2022/

nasa-to-launch-6-small-satellites-to-monitor-study-tropical-cyclones

Image courtesy of Spire Global,

used with permission

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Conclusions

• SmallSats have lower cost, shorter lifecycles, and higher risk profiles than their conventional counterparts
• This opens up a variety of opportunities to provide value to space weather research and operations
• Test new sensors: raise TRL on an operational sensor
• Targeted re-flight of flagship science sensors: fly just-what-you-need for space weather monitoring
• In situ validation of simple sensors: validate hosted sensors with a wandering calibration satellite
• Rapid turnaround on critical needs: demonstrate sensor technology or CONOPS while developing the main mission
• Proliferation of sensors: enables continuous monitoring and monitoring of small-scale phenomena
• A key enabling technology for SmallSat missions in space weather is on-board propulsion to achieve and maintain the desired orbit, and then to dispose at end of mission

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Acronyms

• AC – AeroCube
• AMPERE – active magnetosphere and planetary electrodynamics response experiment
• CIBRE – Colorado inner radiation belt experiment
• CONOPS – concept of operations
• CSSWE- Colorado student space weather experiment
• DPI – deputy principal investigator
• GTOsat – geosynchronous transfer orbit satellite
• LEMUR - low Earth multi-use receiver
• LEO – low Earth orbit
• MagEIS – magnetic electron-ion spectrometer
• uCPT – micro charged particle telescope
• PI – principal investigator
• REACH – responsive environmental assessment commercially hosted
• REMS – relativistic electron magnetic spectrometer
• REPTile – relativistic electron and proton telescope integrated little experiment
• TBD – to be determined
• TRL – technical readiness level

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