NASA's Lucy asteroid probe settles into Earth-orbiting cruise as engineers tackle solar array glitch

Spacecraft crews continue to battle an issue with one the two enormous solar arrays of NASA's new mission, which was launched days after NASA's original mission to investigate a mysterious group if asteroids.
The Lucy spacecraft will fly by eight asteroids. Most of them Trojans, which circle the sun in the exact same orbit as Jupiter, but ahead or behind that massive planet. It will use two solar arrays that are more than 24ft (7m) in size to accomplish this task. After launch on Saturday, Oct. 16, the spacecraft deployed two solar arrays. However, only one of them appeared to have been properly secured when it was released.

Since then, mission personnel have been simultaneously working to evaluate the second solar array as well as to complete the tasks that Lucy requires at this stage in its journey. NASA officials stated Tuesday, Oct. 19, that the spacecraft could continue to operate with the solar arrays in their current configuration and that the glitch wasn't the end for Lucy's mission.

Related: NASA's Lucy spacecraft will visit 8 asteroids

NASA officials stated that the team is continuing its assessment and that an attempt to deploy the entire solar array by the end of next week was planned.

The deployment process took approximately 20 minutes and began an hour after launch. Engineers were aware of this fact from the beginning.

"During deployment there are literally thousands and tiny mechanisms and flexures which are deploying those wings as a Chinese fan," Katie Oakman (Lucy structures and mechanisms lead at Lockheed Martin Space), said during a prelaunch conference.

It seems that one of the steps on a solar array didn't go according to plan. NASA officials stated in the statement that "Analysis currently indicates the second solar array has partially unfurled."

Mission personnel are still trying to figure out how troublesome the array is. The statement continued, "The team continues looking at all available engineering data in order to determine how far it has been deployed." The solar array generates nearly the same power as the fully deployed wing. This power level is sufficient to keep the spacecraft functioning and healthy."

This is not surprising considering Lucy's arrays were designed to provide the spacecraft with much less sunlight than it currently receives. NASA reports that the sun's strength at Jupiter's orbital distance to our star is approximately 25 times less than what we get near Earth.

Oakman stated that the wings are capable of producing 18,000 watts of electricity when they're close to Earth. This would power up my house as well as a few of my neighbors. "But, we have only 500 watts power when we fly to Jupiter Trojan asteroids. That would light only a few bulbs in my living room, and not enough to heat my coffee in the morning.

She also pointed out that Lucy's instruments can collect data during flybys and use only 82 watts.

Engineers are also working on post-launch tasks, as the mission team continues to assess the state of the second Solar array.

According to the release, Lucy required "increased autonomy" and "spacecraft configuration changes" on Tuesday so that it entered cruise mode. It is also using its thrusters for small adjustments to its momentum.

The team won the mission and decided that a backup trajectory correction maneuver was unnecessary. Since the spacecraft is exactly where it needs, they will wait until mid-December to perform the first one.

The spacecraft has not deployed its instrument-pointing platform yet, a concession to the solar array situation. This was scheduled to happen approximately two days after launch.

According to the statement, the Lucy team isn’t certain if the incident will have any long-term consequences for other scheduled activities.