Less than two years after its launch, NASA‘s Psyche spacecraft has experienced a failure in its propulsion system that now jeopardizes its mission to explore a unique metallic asteroid in the main belt. Ever resourceful, NASA engineers have solved the problem of the unexpected pressure drop by switching to a backup line, which they hope will help Psyche reach the asteroid of the same name.
Earlier in April, the Psyche mission engineering team detected an unexpected drop in fuel pressure in the spacecraft’s fuel system. The problem had to be resolved by mid-June, otherwise it could have affected the spacecraft’s flight path to the asteroid Psyche. After an investigation, the team recently switched from the main fuel line to a backup line, which NASA says is identical. The Psyche spacecraft remains on course to meet the asteroid in August 2029.
According to NASA, Psyche’s engines, powered by two large solar panels, ionize and push out xenon gas to gently accelerate the spacecraft. The spacecraft began firing its engines in May 2024, but a little more than a year later, engineers discovered a pressure drop in the line that supplies xenon gas to the engines – from 36 pounds per square inch (psi) to about 26 psi, according to NASA.
After the sudden pressure drop, the team suspended the four electric motors to investigate the problem. NASA engineers conducted extensive testing and diagnostics and discovered that a part inside one of the valves, which opens and closes to control the flow of fuel, had stopped functioning as intended. As a result, the faulty valve was preventing the flow of xenon to the engines.
The team has switched to the backup fuel line and will instruct the spacecraft’s engines to resume operation by mid-June. Mission engineers will keep the backup line valve in the open position to “ensure fuel flow and avoid any potential mechanical problems in the future,” NASA writes.
The mission is scheduled to fly by Mars in the spring of 2026, using the planet’s gravity to guide the spacecraft to the main asteroid belt between Mars and Jupiter. If all goes well, the spacecraft will enter the orbit of the asteroid Psyche in late July 2029 and begin its mission in August of that year.
Psyche launched in October 2023, beginning a 2.2 billion kilometer journey to the metal-rich asteroid located in the main belt. Its journey has been a long time coming and has faced challenges even before launch. The mission was originally scheduled to launch in 2022, but a problem with the spacecraft’s software delayed the mission until the next launch next year. The spacecraft’s software controls its orientation and trajectory, as well as its ability to send and receive data to Earth. One week before the scheduled launch date of October 5, 2023, engineers discovered a problem with the Psyche spacecraft’s engines that could have caused it to overheat during its eight-year mission. As a result, the mission’s launch date was postponed for a week while the team solved the problem.
Psyche is a 140-mile-wide (226-kilometer) asteroid that could be the nucleus of a collapsed planetesimal, one of the building blocks that come together to form a planet. If the mission succeeds in reaching the asteroid, it will be the first to explore an asteroid of this type. We are rooting for you, Psyche.
