A familiar spacecraft tradeoff gets a new workaround
Small satellites are often forced into a propulsion compromise. Chemical systems provide strong bursts of thrust but consume fuel quickly, while electric propulsion can operate with far better efficiency but usually delivers only gentle, sustained pushes. Researchers at MIT now describe a concept that could narrow that gap by using the same propellant in both modes.
The work, reported in the Journal of Propulsion and Power, centers on a hybrid architecture that pairs an electrospray thruster with a chemical rocket mode. The enabling ingredient is ASCENT, a so-called green propellant previously known as AF-M315E.
Why ASCENT is attracting attention
Hydrazine has long been a standard spacecraft propellant, but it is difficult and hazardous to handle. The source text describes it as toxic, carcinogenic, and corrosive, with loading procedures that require extensive protection. ASCENT was developed as a safer alternative and, according to the supplied material, also offers about a 50% increase in specific impulse over hydrazine.
ASCENT had already been flight-tested on NASA's Green Propellant Infusion Mission in 2019. What caught MIT researchers' attention is that it is also an ionic liquid. That matters because ionic liquids can serve as propellants for electrospray thrusters, which generate thrust by extracting charged ions from a liquid and accelerating them into space.
A Lego-sized test with long-duration thrust
To see whether ASCENT would work in this role, the team used a custom test setup with a vacuum chamber and magnetic levitation to mimic space conditions. They loaded just 1 gram of ASCENT into a small reservoir attached to the thruster and applied voltage to produce thrust.
The result was modest in force but important in duration. The experiment generated enough thrust to spin a levitating satellite mock-up, and it continued operating for up to 100 hours. For small satellites, that kind of long-lived, efficient control is valuable for station-keeping, attitude adjustment, and gradual orbital changes.
Why dual-mode propulsion could matter for CubeSats
The real appeal is not merely that ASCENT worked in an electrospray thruster. It is that the same propellant could support both high-thrust and high-efficiency operations in one spacecraft. A CubeSat could, in principle, use chemical propulsion when it needs a sharper maneuver, then switch to electrospray mode for fine control over extended periods.
That would reduce the need to carry separate propulsion systems with different propellants and supporting hardware. For spacecraft where volume and mass are tightly constrained, simplification is a major advantage. It can also expand mission design options by allowing small platforms to do more after deployment.
A useful step, not a finished product
The research does not mean a flight-ready dual-mode engine is about to appear overnight. Testing in a laboratory environment is only one stage, and real spacecraft integration brings challenges in storage, switching logic, thermal behavior, reliability, and total impulse budgeting.
Still, the concept is compelling because it targets a chronic limitation in small-spacecraft design. CubeSats have become increasingly capable sensors, science platforms, and technology demonstrators, but propulsion has often remained one of the hardest constraints. A shared-propellant system that combines maneuvering authority with endurance would make these spacecraft more flexible and more independent.
ASCENT was originally attractive because it reduced handling burdens compared with hydrazine. MIT's work suggests it may also be unusually versatile. If later development confirms that promise, the propellant could help move CubeSat propulsion away from a one-mode-or-the-other mindset and toward a more adaptable model of spacecraft mobility.
This article is based on reporting by Universe Today. Read the original article.
Originally published on universetoday.com