Science

Now that the solar arrays are up and running, Lucy has some sparkling to do.

Now that the solar arrays are up and running, Lucy has some sparkling to do.
Written by admin

A NASA image of the Lucy spacecraft before efforts to fully open one of the solar arrays in May and June.
expand / A NASA image of the Lucy spacecraft before efforts to fully open one of the solar arrays in May and June.

NASA

NASA confirmed this week that Lucy’s mission to explore a series of asteroids has a clean bill of health as it approaches an important gravity assist maneuver in October.

in a new updateThe space agency said Lucy’s solar arrays are “stable enough” for the $1 billion spacecraft to run science operations in the coming years, as it visited 52246 Donaldjohanson, a main belt asteroid, and then flew past eight Trojan asteroids that share those of Jupiter. . Orbit around the sun.

The fate of the Lucy mission has been questioned since the early hours last October when one of the two large solar arrays aboard an Atlas V rocket did not fully open and lock securely. Each of the sequences was intended to open like a hand fan.

Scientists and engineers from the space agency and mission contractors, including spacecraft manufacturer Lockheed Martin and solar array designer Northrop Grumman, gathered hours after launch. At these first meetings, they had “heavy” conversations about the fate of the mission. At the time, engineers weren’t sure why the solar array didn’t turn on, as Lucy’s cameras couldn’t be directed toward the solar array.

Therefore, during these initial meetings, scientists and engineers debated whether the solar array problem could be solved and whether the mission could complete its ambitious scientific observations without two fully functional solar arrays. The partially closed array accounted for about 90 percent of its expected power.

Finally, after months of analysis, testing, and troubleshooting, the team realized that the cord designed to open the solar array was jammed. Lucy is equipped with both primary and backup motors to accommodate the solar arrays, but they are not designed to be co-fired. This spring, engineers decided that the best way out was to fire up both the primary and backup distribution engines for the solar array at the same time, in the hopes that this additional power would unravel the lanyard.

From May 6 to June 16, on seven different occasions, engineers ordered the delivery engines to turn on, and these efforts helped. NASA says the full 360-degree solar array is now open between 353 and 357 degrees. And while not fully locked, it is now under enough tension to function properly during the mission.

Once the solar array issue is seemingly resolved, mission operators can turn their focus to an Earth flyby in October, when Lucy will receive a gravity boost – the first of three to head to the main asteroid belt. As part of this fuel-efficient trajectory, Lucy will fly towards its first target in April 2025, the main belt asteroid named after the American anthropologist Donald Johanson, who co-discovered the famous “Lucy” fossil in 1974. A female hominin species that lived about 3.2 million years ago supported the evolutionary idea that bipedalism preceded an increase in brain size.

The Lucy asteroid mission is also named after the famous fossil. Scientists then visit the eight Trojan asteroids, hoping to gather information about the building blocks of the Solar System and better understand the nature of their planets today.

No probe has flown by these small Trojan asteroids, which cluster at stable Lagrangian points behind and in front of Jupiter’s 5.2 astronomical unit orbit from the Sun. Asteroids are mostly dark but may be covered in tholins, organic compounds that could provide the raw material for life’s basic chemicals.

About the author

admin

Leave a Comment