WASHINGTON — NASA is suspending efforts, at the least till late subsequent 12 months, to attempt to absolutely deploy a photo voltaic array on its Lucy spacecraft, citing diminishing returns because the spacecraft heads away from the solar.
In a statement quietly posted on NASA’s web site Jan. 19, the company stated the most recent effort to latch one in every of two photo voltaic arrays on Lucy, greater than a month earlier, failed to finish the deployment of the round array and lock it into place. That effort, NASA stated, “produced solely small motion within the photo voltaic array.”
The mission has been working to completely deploy the photo voltaic array since shortly after its launch in October 2021. Whereas one of many arrays, 7.3 meters in diameter, unfolded and latched into place as designed, the opposite didn’t. Engineers spent months diagnosing the issue, concluding a loss in tension in a lanyard used to deploy the array kept it from fully unfolding and latching into place.
NASA has performed down the issue, noting that engineers consider the array is nearly utterly unfolded and seems to be secure. That was based mostly on the array’s efficiency throughout a gravity-assist flyby of the Earth Oct. 16, when it handed lower than 400 kilometers above the Earth, via the tenuous higher reaches of the environment, with no points.
Nonetheless, spacecraft controllers have tried since that flyby to attempt to full the array’s deployment and lock into place. One try Nov. 7 “deployed the wing incrementally ahead,” NASA stated, however controllers additionally observed a small vibration within the array, which engineers concluded was the results of an interplay between the motor and the structural modes of the array.
After adjusting the motor, NASA tried once more Dec. 13, however observed that progress had “decreased to minimal ranges,” which engineers concluded was because of the dropping temperatures as Lucy strikes farther from the solar.
“NASA’s Lucy mission crew has determined to droop additional photo voltaic array deployment actions,” the company stated in its newest assertion. “The crew decided that working the mission with the photo voltaic array within the present unlatched state carries a suitable stage of danger and additional deployment actions are unlikely to be useful right now.”
The company has not dominated out one other try to lock the array, however not till the spacecraft makes its subsequent shut strategy to the Earth in late 2024, warming it sufficient to make progress extra possible. These plans can even rely on the soundness of the array through the first maneuver by the spacecraft’s foremost engine in February 2024.
Even when the array doesn’t absolutely unfold and latch, NASA stated that the array, 98% deployed, can generate sufficient energy for the spacecraft to finish its mission, flying by one foremost belt asteroid and 7 Trojan asteroids at Jupiter’s distance from the solar. These flybys will happen between 2025 and 2033.