Updated 9 a.m. Eastern June 17 with NASA cost estimate.

WASHINGTON — A NASA mission to a metallic asteroid has passed a major review, but questions remain about its ability to remain on budget and schedule.

NASA announced June 11 that the Psyche mission had been cleared to proceed into Phase C of its development, which includes final system design as well as assembly and testing of the spacecraft and its instruments. The mission had completed a preliminary design review earlier this year.

“The Psyche team is not only elated that we have the go-ahead for Phase C, more importantly we are ready,” said Lindy Elkins-Tanton of Arizona State University, the principal investigator for the mission, in a statement. “With the transition into this new mission phase, we are one big step closer to uncovering the secrets of Psyche, a giant mysterious metallic asteroid, and that means the world to us.”

Psyche, part of NASA’s Discovery program of lower-cost planetary science missions, is scheduled to launch in August 2022 on a vehicle yet to be selected to fly to the main belt asteroid of the same name. After a Mars flyby in 2023, it will arrive at the asteroid in January 2026. The spacecraft will spend at least 21 months orbiting the asteroid, more than 200 kilometers in diameter and comprised primarily of iron and nickel. The asteroid, scientists have proposed, could be the remnant of the core of much larger body that broke apart during the formation of the solar system.

While project officials say the mission is on track for launch, it is not without issues. A report on major NASA programs published by the Government Accountability Office in May highlights several technical and programmatic issues with Psyche. That included concerns that the spacecraft will experience higher launch loads than some of its instruments are rated for.

The spacecraft is using a camera based on one flown on the Curiosity Mars rover. While the instrument is considered “heritage” and thus doesn’t pose development challenges, the GAO report noted that the instrument will experience higher shock levels during launch on this mission because of its location on the spacecraft. “As a result, qualification testing may be required to resolve the technical issue at increased cost and schedule risk,” the GAO concluded.

Another instrument, a gamma-ray and neutron spectrometer, is also expected to face higher mechanical and dynamic loads on Psyche than it had previously been qualified for. “The project and its contractors are conducting design analysis and investigating alternative mounting options, such as a deployable boom, to reduce vibration levels,” the GAO report stated.

In addition to its scientific instruments, Psyche is carrying a NASA technology demonstration called Deep Space Optical Communications, demonstrating the use of lasers to provide high-bandwidth communications. NASA’s Space Technology Mission Directorate is funding development of that payload, but the GAO noted that its late delivery could be a threat to the mission’s schedule.

The review Psyche just completed, formally known as Key Decision Point C, is the point at which NASA makes a formal cost and schedule commitment for a project, typically using the joint confidence level methodology. That commitment is usually made at the 70 percent confidence level, meaning the project believes there is a 70 percent chance the mission will be ready for launch no later the scheduled date and no higher than the projected cost.

While the announcement about the review confirmed the August 2022 launch date, it did not mention the cost commitment expected in a KDP-C review. NASA spokesperson JoAnna Wendel said June 17, in response to a SpaceNews inquiry several days earlier, that the review set a total lifecycle cost for the mission of $996.4 million.

The GAO report included a cost range of $907.3 million to $957.3 million for Psyche, while noting that cost and schedule baselines would be specified at the KDP-C review. NASA’s fiscal year 2020 budget proposal, released in February, included the same cost range. NASA requested $213.2 million for the mission in that 2020 budget, its peak year of funding.

Another issue for Psyche is access to staffing and other resources at the Jet Propulsion Laboratory, the lead center for the mission. The mission could be forced to conduct integration and testing off-site because the Europa Clipper mission, being prepared for a 2023 launch, plans to use the same clean room but has stricter cleanliness requirements.

The GAO report cited “staffing shortfalls” at JPL that has delayed systems engineering work and software development for the mission. “The project is working to acquire additional systems engineering support and replan the schedule to accommodate software delays,” the report stated.

Psyche is not the only JPL mission affected by staffing issues. A lack of available engineering staff was one of the major reasons NASA pushed back the launch of Europa Clipper from 2022 to 2023, an issue noted in a report on the mission by NASA’s Office of Inspector General May 29.

Staffing shortages at JPL came up during a June 11 hearing of the House Science Committee’s space subcommittee. “We’re right now finishing off the Mars 2020 lander and, frankly, the top talent is working on that, pushing it over the finish line,” said Thomas Zurbuchen, NASA associate administrator for science. “Some of the people we were going to put on the next mission are working to finish off Mars 2020. That has to be the highest priority.”

Some in the science community have wondered by NASA doesn’t increase the size of the engineering workforce at JPL to accommodate the crunch of missions. Zurbuchen appeared to resist those calls at the House hearing. “What I don’t want to do is increase, necessarily, the center size,” he said. “What I want to do is think about how we distribute the work and how we space strategic-scale missions relative to each other to make sure that we don’t step on each other’s feet.”