Asteroid probe mounted on Atlas booster originally assigned to astronaut flight

Asteroid probe mounted on Atlas booster originally assigned to astronaut flight

A crane raises the Lucy spacecraft, encapsulated inside its payload fairing, atop an Atlas 5 rocket Thursday. Credit: United Launch Alliance

Teams at Cape Canaveral transferred NASA’s Lucy asteroid explorer to a United Launch Alliance integration building Thursday and mounted the robotic science probe atop an Atlas 5 rocket for liftoff later this month, using a booster originally built to send astronauts into space.

The 3,300-pound (1,500-kilogram) Lucy spacecraft, built by Lockheed Martin, is set for launch Oct. 16, the first opportunity in a 23-day launch period to begin a 12-year sojourn through the solar system.

The robot’s primary science goal is to conduct the first close-up flybys of a group of distant asteroids called the Trojans located ahead of and behind Jupiter in its orbit around the sun.

The Lucy spacecraft was encapsulated inside the payload fairing of its Atlas 5 rocket at the Astrotech processing facility in Titusville, Florida. ULA transported the science probe, inside its fairing, from Astrotech to the Vertical Integration Facility at Cape Canaveral Space Force Station early Thursday.

A crane raised the payload on top of the Atlas 5, competing the build-up of the 188-foot-tall (57-meter) rocket.

The 75-minute launch window Oct. 16 opens at 5:34 a.m. EDT (0934 GMT). The Atlas 5 rocket launching Lucy will fly in its basic configuration, without any strap-on solid rocket boosters.

Mission managers in August reassigned the Atlas 5’s first stage booster from the Starliner program to the Lucy mission. The Atlas 5 was already stacked on its launch platform at Cape Canaveral, and ready for blastoff with a Starliner spacecraft to begin an unpiloted test flight to the International Space Station.

But engineers grounded the Starliner spacecraft after finding stuck valves in the capsule’s propulsion system. Ground crews removed the spacecraft from the top of its Atlas 5 rocket and returned the Starliner to Boeing’s factory at nearby Kennedy Space Center for troubleshooting.

NASA’s Lucy spacecraft moves toward the Atlas 5 rocket’s Vertical Integration Facility at Cape Canaveral early Thursday. Credit: Alex Polimeni / Spaceflight Now

After the most recent delay, the launch of Boeing’s demonstration mission, called Orbital Flight Test-2, is not expected before next year. The OFT-2 mission is a re-do of Boeing’s first Orbital Flight Test in 2019, which ended prematurely after software problems prevented the Starliner spacecraft from reaching the space station.

Once OFT-2 flies, and assuming it’s a successful mission, NASA will clear Boeing’s Starliner for its first test flight with astronauts. That is now scheduled some time later in 2022, at the earliest.

With the Starliner missions delayed to next year, officials agreed to reassign the Atlas 5 first stage already standing on ULA’s launch platform from the OFT-2 mission to Lucy.

The same 107-foot-tall (32-meter) core stage, which ULA delivered to Cape Canaveral in 2019, was originally supposed to launch the first crew flight on Boeing’s Starliner spacecraft. But ULA and NASA had already reassigned the Atlas first stage to the OFT-2 mission after Boeing decided to launch a second unpiloted Starliner demonstration flight, following the troubled OFT-1 mission.

Omar Baez, NASA’s launch director for the Lucy mission, said engine problems on the Atlas 5 first stage originally slated to launch the Lucy spacecraft drove the decision swap rockets with OFT-2.

“It was unfortunate that OFT-2 had its malfunctioning valve problems way late in the game,” Baez said. “And lucky, we were able to take lemons and make lemonade out of it.”

Baez said the RD-180 engine on the Atlas first stage built for the Lucy mission failed a hydraulic system checkout at ULA’s factory. The problem delayed delivery of the rocket to Cape Canaveral for launch processing.

“It failed one our checks for actuating the Russian engine,” Baez told Spaceflight Now in an interview.

“So we had to swap to swap out an engine set,” Baez said. “After we did the changeout, we ran it through the checkout, and it also showed the same type of occurrence.”

The engine on the Atlas first stage that was supposed to launch Boeing’s OFT-2 mission passed a similar hydraulic test, and was good to go.

NASA’s Lucy spacecraft moves toward the Atlas 5 rocket’s Vertical Integration Facility at Cape Canaveral early Thursday. Credit: Alex Polimeni / Spaceflight Now

Officials opted to detach the OFT-2 launch vehicle’s dual-engine Centaur upper stage and two solid rocket boosters. The Atlas 5’s main stage remained on the launch platform for use on the Lucy mission.

Workers raised a different Centaur upper stage with a single RL10 engine for the Lucy mission, which doesn’t require any solid-fueled rocket motors for an additional boost.

“It’s been a long time since we had to take a Centaur down, since early on in the Atlas program,” Baez said.

“It was a two solid rocket motor configuration, so we had to remove those. We had to terminate some of the cabling and the destruct system that goes along with that,” he said. “We did have to change some of the avionics boxes because of the different configuration.”

ULA completed the reconfiguration of the Atlas 5 rocket for Lucy at Cape Canaveral while the company prepared to launch a different Atlas 5 mission from California with the Landsat 9 remote sensing satellite last month.

“The team really worked hard to get that done quickly and efficiently while trying to maintain the Lucy window.”

Baez said NASA’s Launch Services Program at Kennedy, which provides oversight for rocket missions carrying the agency’s science probes, also serves the Commercial Crew Program that manages Boeing’s Starliner test flights.

The reassignment of the Atlas 5’s first stage was not the first time ULA had to swap rocket components for the Lucy mission. A leak in a Centaur upper stage tank forced managers earlier this year to use a different Centaur stage for Lucy, according to Baez.

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