NASA SEES MATRIX Team Models Propellant Gauging for IM-3 Mission

High School Interns Map Lunar Propellant Windows for Intuitive Machines Mission

High school students participating in the NASA STEM Enhancement in Earth Science program developed an interactive dashboard for the upcoming IM-3 lunar mission, Mirage News reported. Working at the University of Texas Center for Space Research during the summer of 2026, the eight-member MATRIX team built computational models to measure propellant mass in microgravity conditions.

The Tech TL;DR:

• The student team reconstructed flight paths for NASA’s IM-1 and IM-2 missions using public navigation data from the Jet Propulsion Laboratory to build an accurate trajectory algorithm for the unreleased IM-3 path.
• Computational fluid dynamics simulations and Monte Carlo methods allowed the interns to model fuel slosh and predict operational windows for Modal Propellant Gauging.
• The analysis demonstrated that acoustic propellant gauging can take reliable readings during critical lunar orbit insertion and powered descent burns ahead of the 2027 landing.

Reconstructing Lunar Trajectories from Public Data

Because a complete flight trajectory for the IM-3 mission remains unpublished, the intern group engineered a custom reconstruction algorithm. The students relied entirely on public records, incorporating detailed trajectory files provided by the NASA Jet Propulsion Laboratory’s Navigation and Ancillary Information Facility for the earlier IM-1 and IM-2 flights. By contrasting the actual flight path of the IM-2 spacecraft against a theoretical unpropelled model, the team isolated engine burns and calculated the velocity changes tied to each ignition.

Liquid fuel behavior in low gravity presents a persistent engineering hurdle, as propellant clings to tank walls rather than settling at the base. To address this, the team executed computational fluid dynamics simulations to evaluate slosh dynamics inside the tanks alongside Monte Carlo simulations mapping out potential propellant states. Mentored by Dr. Kevin Crosby from Carthage College, the students focused on Modal Propellant Gauging, a technique developed at Carthage College that evaluates the acoustic response of fuel tanks to estimate remaining mass.

# Example trajectory parameter variation logic used in dashboard modeling
def calculate_propellant_margin(initial_mass, burn_velocity, efficiency):
    dry_mass = 450.0 # kg baseline estimate
    fuel_remaining = initial_mass - (burn_velocity * efficiency)
    return max(fuel_remaining - dry_mass, 0.0)

Identifying Reliable Measurement Windows for Landing

The team’s analytical models revealed that Modal Propellant Gauging can acquire reliable measurements during the two primary lunar burns, specifically Lunar Orbit Insertion and Powered Descent, as well as intermittently during Descent Orbit Insertion. According to the team’s findings, the starting mass of the spacecraft exerted the strongest influence over the duration of each gauging window.

In addition to timing the fuel readings, the MATRIX team evaluated candidate launch opportunities for 2027 and generated a landing distribution analysis for the target site at Reiner Gamma. The student group presented their methods and findings directly to the propulsion engineering group at Intuitive Machines. Their research, titled “Computational Models to Estimate Modal Propellant Gauging (MPG) Windows on the Intuitive Machines IM-3 Mission,” was shared at the SEES Annual Symposium and the Wisconsin Space Grant Consortium Annual Conference.

This high school team, in a period of less than a month, developed a depth of understanding and facility with advanced methods that rivals advanced graduate students in the field, said Dr. Kevin Crosby, describing the group’s work.

The team is scheduled to present their findings again at the American Geophysical Union Annual Meeting in San Francisco in December 2026. The research provides data directly relevant to in-space propellant management, a capability required for orbital fuel depots and future exploration.