NASA's Lucy asteroid spacecraft is on its way, but engineers are looking into telemetry that suggests one of the probe's two circular solar arrays may not be fully unfurled and locked in place, according to a blog post published on Sunday by the agency.
Lucy was launched early Saturday from Cape Canaveral atop a United Launch Alliance Atlas 5 rocket on a trajectory that would send the spacecraft out to a cluster of asteroids sharing Jupiter's orbit in 2022 and 2024, with two velocity-boosting gravity-assist Earth flybys in 2022 and 2024.
"Lucy's two solar arrays have deployed, and both are producing power and the battery is charging," NASA wrote in a blog post. "While one of the arrays has latched, indications are that the second array may not be fully latched."
Lucy will be farther away from the sun than any other solar-powered spacecraft before it, and its two arrays, which are designed to unfold 360 degrees like Chinese fans, are critical to the mission's success.
Lockheed Martin Space built the arrays, which have a total of 51 square meters of solar cells. Because the spacecraft will be going out to Jupiter's distance from the sun, where sunlight is just a fraction of what it is on Earth, the enormous area is required.
"That enables Lucy to travel further away from the sun than any other solar-powered spacecraft to date," Katie Oakman, Lucy structures and mechanisms lead at Lockheed Martin Space, said.
Lucy's panels can create 18 kilowatts of power in close proximity to the Earth. However, when flying by the Trojan asteroids, the arrays will only provide 500 watts of power, which will be more than enough to power the spacecraft and its three major instruments.
Lucy's ultimate goal is to investigate the Trojan asteroids, a group of asteroids in Jupiter's orbit that have never been thoroughly explored.
At Jupiter's "Lagrangian points," these Trojan asteroids travel in massive swarms, or camps. The Lagrangian points are areas where gravity's push and pull hold the camps in place, leading and behind Jupiter in its perpetual orbit around the sun.
The collection of amorphous space rocks is akin to a collection of cosmic fossils, offering a glimpse into our solar system's early days, some 4.6 billion years ago. Lucy will take on the role of a cosmic palaeontologist, flying past the eight "fossils" from afar and analyzing their surfaces using infrared imagers and cameras.