NASA's newest asteroid mission, a spacecraft targeting space rocks that orbit ahead of and behind Jupiter, is ready to begin its journey.
Called Lucy, the mission is scheduled to launch on Saturday (Oct. 16) at 5:34 a.m. EDT (0934 GMT) aboard a United Launch Alliance Atlas V rocket from Cape Canaveral Space Force Station in Florida. You can watch the launch live at Space.com courtesy of NASA, with coverage starting at 5 a.m. EDT (0900 GMT).
"This team has put in so much work to build a spacecraft that is truly a work of art," Donya Douglas-Bradshaw, the Lucy project manager at NASA's Goddard Space Flight Center in Maryland, said during a news conference held on Wednesday (Oct. 13). "The spacecraft work is complete, it's been powered on, the team is monitoring it and we are ready to launch."
The launch will kick off a 12-year journey during which the Lucy spacecraft will swing past eight different asteroids in hopes of helping scientists understand how our solar system came to be the way it is today.
Most of those asteroids belong to a category called Trojans, which are trapped in gravitationally stable points of a planet's orbit. Lucy's targets are Trojan asteroids that orbit with Jupiter, one clump about 60 degrees ahead of the planet and the other about 60 degrees behind it, a cosmic posse befitting the solar system's largest planet.
The $981 million Lucy mission will give scientists their first-ever up-close look at any Trojan, but on top of that, the mission is carefully designed to give scientists a taste of the range of rocky bodies in the region. In the long term, scientists hope that the mission will give them a better sense of how the solar system reached its present arrangement.
But before Lucy can tackle any science, it has to bid farewell to Earth and the humans who built it.
"I'm really excited, but I'm also a little sad," Cathy Olkin, the mission's deputy principal investigator and a planetary scientist at the Southwest Research Institute (SwRI) in Colorado, told Space.com shortly after the spacecraft was loaded into the fairing in preparation for launch. "I know that it's preparing for its journey and this is what we built it to do."
Lucy won't be riding quite the rocket that the United Launch Alliance (ULA) had in mind. The company was also due to launch an uncrewed test flight dubbed OFT-2 of Boeing's Starliner capsule to the International Space Station this summer, but Boeing had to retreat from the launch pad to address a valve issue in the spacecraft.
"We were able to make that a positive in that we were able to use the OFT[-2] booster and convert it for use for Lucy," Omar Baez, launch director for Lucy at NASA's Launch Services Program at Kennedy Space Center in Florida, said during the news conference.
Converting the booster required removing two solid rocket motors, replacing an avionics box and a few other modifications to support a fairing in place of a capsule, he and ULA Chief Operating Officer John Elbon noted.
"I think overall it ended up in a situation that worked out really well," Elbon said of the switch.
The Lucy team is hoping to get the mission on its way as early in the three-week launch period as possible to ensure the spacecraft can get on its way. Fortunately, the weather forecast looks quite promising for the mission's approximately 75-minute launch window on Saturday, according to the mission's launch weather officer, Jessica Williams of the 45th Weather Squadron, who called it "a beautiful morning for launch" during the news conference.
If the mission can't launch on its first opportunity, things begin to look a little grimmer: The spacecraft's Sunday (Oct. 17) opportunity offers just a 50% chance of cooperative weather as tall cumulus clouds and rainshowers threaten; meanwhile, Monday offers 60% odds of favorable weather for launch due to lingering showers and winds.
After launch, Lucy will conduct two flybys of Earth to adjust its trajectory and send the mission out through the solar system. The spacecraft will make its first flyby in April 2025, of a main-belt asteroid called Donaldjohanson; the first Trojan flyby will occur in August 2027. Most of the mission's visits will occur in 2027 and 2028; its final planned flyby will take place in March 2033.
However, the spacecraft's trajectory will continue carrying it between the two Trojan swarms for about a million years; the first extra loop or two may yield additional science results if the spacecraft remains in good condition.
First, of course, Lucy has to launch.
"I'm feeling really good about it," Kevin Berry, an aerospace engineer at Goddard Space Flight Center and flight dynamics team leader for the Lucy mission, told Space.com. "We're in amazing shape and I'm just excited about getting out there and actually navigating to things."