SwRI and UTD collaborate on space sensor testing

SwRI and UTD collaborate on space sensor testing
by Clarence Oxford
Los Angeles CA (SPX) Jul 17, 2024

Researchers from Southwest Research Institute (SwRI) and The University of Texas at Dallas (UTD) are working together to test an advanced sensor aimed at measuring neutral gas velocities in the Earth's upper atmosphere. The project, under the leadership of Dr. Joo Hwang from SwRI and Dr. Phillip Anderson from UTD, is funded by the new SwRI/UTD Seed Projects for Research, Innovation, and Technology (SPRINT) Program. Another SPRINT initiative is investigating domestic lithium independence by examining tectonic influences on emerging lithium deposits.

Geospace, which encompasses the Earth's upper atmosphere and adjacent outer space, features both ionized and neutral elements known as the ionosphere and thermosphere, respectively. Neutral winds are the main drivers of this region's dynamics, playing a crucial role in the distribution of mass, momentum, and energy, and influencing geospace weather across 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," said Hwang, a staff scientist in SwRI's Space Science Division. "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."

This project provides a valuable chance to verify the sensor's performance and demonstrate its technical readiness, which could increase its chances of being selected for future missions. The combination of new sensor technologies and molecular beam testing methods highlights an innovative approach to addressing key gaps in understanding space weather impacts.

"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," said Anderson, director of UTD's William B. Hanson Center for Space Sciences. "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."

The only other MBF is located at the University of Bern in Switzerland. SwRI has used its expertise to establish a molecular beam accelerator at its San Antonio headquarters to meet the need for a domestic facility to verify the functionality and effectiveness of similar space sensors.

The facility generates a neutral gas beam at velocities of 3-6 kilometers per second, temperatures up to 1,000 C, and pressures of hundreds of pounds per square inch to mimic the movement of instruments in thin atmospheres. A small 10-micron opening produces a narrow gas beam in the expansion chamber, where a skimmer with a one-millimeter orifice and a filter can create a higher velocity tail. Adjusting the nozzle-skimmer distance controls the beam's downstream width and flux, while large turbomolecular pumps maintain a high vacuum.

"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," Hwang said. "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 developed SPRINT to foster greater scientific and engineering collaboration between the two institutions. This program allows researchers to work together on issues of mutual interest and need, combining their capabilities, facilities, and expertise. Funded projects must include at least one principal investigator from each institution.