WASHINGTON — NASA is suspending efforts, at least until late next year, to try to fully deploy a solar array on its Lucy spacecraft, citing diminishing returns as the spacecraft moves further from the sun .
In a statement quietly posted on the NASA website on January 19, the agency said the latest effort to lock down one of the two solar panels on Lucy, more than a month earlier, had not been successful. completing the deployment of the circular panel and locking it in place. This effort, NASA said, “produced only a small movement in the solar array.”
The mission has been working on the full deployment of the solar panel since shortly after its launch in October 2021. While one of the panels, 7.3 meters in diameter, unfolded and locked in place as planned, the other didn’t. Engineers spent months diagnosing the problem, concluding that a loss of tension in a lanyard used to deploy the array was preventing it from fully deploying and locking into place.
NASA played down the issue, noting that engineers believe the array is almost completely unfolded and appears stable. This was based on the array’s performance during a gravity-assisted flyby of Earth on October 16, when it passed less than 400 kilometers above Earth, through the thin upper parts of the atmosphere. , no problem.
However, spacecraft controllers have attempted since that flyby to try and complete the deployment of the array and lock it in place. An attempt on Nov. 7 “deployed the wing gradually forward,” NASA said, but controllers also noticed a small vibration in the array, which engineers said was the result of an interaction between the engine and the structural modes of the network.
After adjusting the engine, NASA tried again on December 13, but noticed that progress had “diminished to minimal levels”, which engineers concluded was due to falling temperatures as Lucy s away from the sun.
“NASA’s Lucy mission team has decided to suspend further solar array deployment activities,” the agency said in its latest statement. “The team has determined that operating the mission with the solar array in the current unlocked state carries an acceptable level of risk and that further deployment activities are unlikely to be beneficial at this time.”
The agency has not ruled out another attempt to lock down the network, but not before the spacecraft makes its next close approach to Earth in late 2024, warming it up enough to make progress more likely. These plans will also depend on the stability of the array during the first maneuver of the spacecraft’s main engine in February 2024.
Even if the array doesn’t fully unfold and lock, NASA said the array, 98% deployed, can generate enough power for the spacecraft to complete its mission, flying past an asteroid of the main belt and seven Trojan asteroids at Jupiter’s distance from the sun. These overflights will take place between 2025 and 2033.