Reviewed by Lexie CornerJul 17 2024
Southwest Research Institute (SwRI) and The University of Texas at Dallas (UTD) researchers are working together to test a next-generation sensor for measuring neutral gas velocities in the Earth's high atmosphere. The study, directed by SwRI's Dr. Joo Hwang and UTD's Dr. Phillip Anderson, is funded by a grant from the new SwRI/UTD Seed Projects for Research, Innovation, and Technology (SPRINT) Program.
Through a new collaborative program, Southwest Research Institute’s new Molecular Beam Facility (MBF) will verify and enhance the measurement capabilities of UT-Dallas’ Neutral Wind Meter. The only other MBF is at the University of Bern in Switzerland, so SwRI’s MBF is a critical domestic facility necessity for a domestic facility to verify the functionality and effectiveness of similar space sensors. Image Credit: SwRI
Another SPRINT project is investigating domestic lithium independence, specifically tectonic restrictions on major new lithium resources.
Geospace, the border zone between the Earth's upper atmosphere and adjacent outer space, has ionized and neutral components, known as the ionosphere and thermosphere, respectively. Neutral winds predominantly control the region’s dynamics, acting as key regulators and redistributors of mass, momentum, and energy while also generating geospace weather at all latitudes.
Understanding the dynamics of neutral wind and its coupling with ionospheric plasmas is critical for protecting military and commercial space-based assets in low Earth orbit from space weather events. We will leverage our new Molecular Beam Facility (MBF) to validate and enhance the measurement capabilities of UTD’s Neutral Wind Meter (NWM), establish development procedures, and significantly improve the signal-to-noise ratio.
Dr. Joo Hwang, Staff Scientist, Space Science Division, Southwest Research Institute
The project provides a rare opportunity to validate sensor performance and demonstrate technical readiness, increasing the instrument's chances of being picked for future missions. The combination of novel sensor technologies and molecular beam testing procedures demonstrates a well-thought-out and unique strategy for addressing crucial gaps in understanding space weather consequences.
Protoflight sensor hardware has been constructed and tested in the laboratory environment, and numerical simulations have confirmed the instrument’s operational principles and robust approach for measuring neutral gas velocities. The opportunity to test it in an environment that simulates the actual conditions in space is extremely valuable. A version of our instrument scheduled to fly for the first time on a rocket in 2025 will be evaluated at SwRI early next year.
Dr. Phillip Anderson, Director, William B. Hanson Center for Space Sciences
The only other MBF exists at the University of Bern in Switzerland. SwRI has used its unique ability to build a molecular beam accelerator in its San Antonio headquarters, addressing the crucial need for a domestic laboratory to test the operation and efficacy of comparable space sensors.
To replicate the motion of equipment in tenuous atmospheres, the facility generates a neutral gas beam at velocities ranging from 3-6 kilometers per second, temperatures up to 1,000 degrees Celsius, and pressures of hundreds of pounds per square inch.
A small 10-micron hole directs a narrow beam of gas into the expansion chamber, where the middle section is recovered by a skimmer with a one-millimeter orifice and a filter capable of producing a higher velocity tail.
Adjusting the nozzle-skimmer distance can control the downstream width and flux of the beam, while large turbomolecular pumps maintain a high vacuum.
Hwang added, “SwRI will optimize settings for UTD’s NWM, determining the velocity filter settings needed to create a molecular beam close to the relative velocity of the neutral gas spacecraft experience in low-Earth orbit. Through dedicated testing with updated software, MBF will verify/support the measurement capabilities of UTD’s NWM.”
SwRI's Executive Office and UTD's Office of Research and Innovation created SPRINT to foster better scientific and engineering collaboration between the two institutions. The program allows researchers to collaborate on subjects of mutual interest and need while combining both organizations' capabilities, facilities, and experience. Each institution contributes at least one principal investigator to the funded projects.