NASA recently tested a lithium-fed magnetoplasmadynamic (MPD) thruster that reached 120 kilowatts — a milestone the agency says is a step toward reducing crewed Mars transit time and the radiation exposure that comes with it. No demonstration mission launch date has been confirmed.
How It Works
The MPD thruster ionizes lithium metal vapor and accelerates the resulting plasma through a magnetic field, generating continuous thrust over weeks rather than a single chemical burn. That sustained push builds far higher terminal velocity than conventional rockets allow.
At 120 kilowatts, the tested system dwarfs NASA’s current operational electric propulsion hardware — the 12-kilowatt Hall thrusters powering the Lunar Gateway’s Power and Propulsion Element (PPE), which itself tops out at 50 kW for Hall-effect output. Higher sustained power directly raises specific impulse, the standard measure of propellant efficiency in space propulsion.
MEA did not respond by publication time regarding India’s scientific engagement with this programme.
“High-power electric propulsion is a critical technology for enabling human exploration beyond the Moon and toward Mars.”
NASA · NASA official statement · 2026
The Radiation Problem
Radiation exposure remains the single largest health barrier to crewed Mars missions. Longer transits mean longer exposure windows in deep space, where Earth’s magnetic field offers no protection. Cutting transit time is therefore as much a medical calculation as an engineering one.
SpaceX’s Starship — the Human Landing System for NASA’s Artemis architecture — uses liquid methane and liquid oxygen chemical propulsion. Conventional transits to Mars using chemical propulsion target six to nine months; published studies have explored 90-day Starship transits, though no mission profile at that duration is formally baselined.
India’s Stake
ISRO’s Mangalyaan Mars Orbiter Mission, launched in 2013 at ₹450 crore, used conventional propulsion and took 298 days to reach Martian orbit. ISRO has conducted early-stage electric propulsion research but has not flown any MPD or Hall-effect thruster on an operational mission.
India signed NASA’s Artemis Accords in June 2023, opening a formal pathway for deep-space technology collaboration. The Department of Space received ₹12,543 crore in Union Budget 2025-26 — a 9 percent rise over the prior year — with a portion earmarked for advanced propulsion research. A proven high-power plasma standard from NASA could directly inform ISRO’s propulsion roadmap as it plans missions beyond Gaganyaan.
ℹ️ Background: Magnetoplasmadynamic Thrusters
- MPD thrusters use electromagnetic force — not just electrostatic acceleration — to expel plasma, enabling higher power densities than Hall-effect designs.
- First explored by the Soviet Union and the US in the 1960s-70s; never previously flown at 120 kW.
- This thruster uses lithium metal vapor as propellant — not xenon, which is standard in commercial Hall-effect satellite thrusters.
- Lithium’s higher atomic mass and ionization properties make it better suited to very high-power regimes than xenon.
What Happens Next
NASA’s propulsion funding falls under the fiscal year 2027 budget cycle; congressional appropriations hearings are scheduled for late 2026. ISRO’s Space Science and Technology Advisory Council meets quarterly — its next session is due in July 2026, where advanced propulsion options are on the standing agenda.
FAQ
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