Orbiting between Mars and Jupiter, the metal-rich asteroid Psyche is set to welcome NASA's spacecraft in 2026. For the first time in deep space, the mission will harness Hall effect thrusters—a breakthrough in propulsion technology.
Nestled in the asteroid belt, 16 Psyche stands out at 220 kilometers in diameter, composed almost entirely of iron and nickel. While its metals are valued at an astonishing 10,000 quadrillion dollars, NASA's interest lies in its scientific potential as a window into solar system history.
Psyche may represent the exposed core of a long-destroyed planet akin to Mars. It's also the first metallic body NASA has targeted, unlike previous missions to rocky or icy objects.
Launched in August 2023 aboard a SpaceX Falcon 9—with Mars gravity assist—the spacecraft will rely on Hall effect thrusters post-deployment. This innovative system makes the ambitious journey feasible.
Chemical rockets excel at escaping Earth's gravity but guzzle fuel. In space, efficiency reigns, leading to electric propulsion powered by solar panels that ionize and accelerate gas for sustained thrust.
NASA has honed this with missions like Deep Space 1 (1998) and Dawn (2007), which explored Vesta and Ceres using ion thrusters. These ionize xenon gas via electron bombardment, creating plasma accelerated by electric fields between polarized grids.
Hall effect thrusters innovate by generating the electric field through a magnetic field and voltage difference between anode and cathode, offering reliable performance.
Common on Earth-orbiting satellites, their deep-space debut with Psyche addresses challenges like diminishing solar power farther from the Sun and demands of prolonged operation.
Chemical propulsion would demand five times more fuel, ballooning the spacecraft beyond Cassini—the Saturn explorer (2004-2017) that cost $4 billion, reserved for flagship efforts.
Psyche isn't a top-priority juggernaut, so Hall thrusters enabled a compact design under $1 billion—streamlining launch and execution while advancing deep-space capabilities.
