BUSAN, South Korea — NASA has canceled the mission of a robotic lunar rover that would have searched for ice at the moon’s south pole, citing development delays and cost overruns.
NASA announced on July 17 that it will end development of the Volatiles Investigating Polar Exploration Rove (VIPER) mission. The rover, to be sent to the moon’s south polar region on Astrobotic Technology’s commercial lander called Griffin, would survey the terrain, including permanently shadowed areas, to better understand the extent and form of water ice there.
At a briefing to announce the cancellation, agency officials said VIPER costs had increased by more than 30%, prompting the agency’s review of the termination. NASA confirmed VIPER in 2021 at a cost of $433.5 million. Joel Kearns, deputy associate administrator for exploration at NASA’s Science Mission Directorate, said the most recent estimate was $609.6 million, with a September 2025 launch.
“In this case, the projected remaining cost of VIPER would result in the need to cancel or interrupt many other missions in our Commercial Lunar Payload Services pipeline,” said Nicky Fox, NASA’s associate administrator for science. “That is why we have decided to abandon this particular mission.
Kearns said VIPER has suffered from a series of supply chain issues that have delayed deliveries of key, unspecified components dating back to the pandemic. “There were delays over and over again for several key components,” he said, with small, incremental delays that were more difficult for the mission to plan for than one large delay.
This complicated the construction of the rover, which he described as the size of a small car that is built from the inside out. “A lot of the components that were delayed were actually internal to VIPER, so as the components got delayed, it started to force the VIPER team to delay assembly and delay integration and initial testing.”
The rover is now complete, but is only now beginning environmental testing. Kearns said the revised cost and schedule assume VIPER will pass that environmental testing without issue. “I will tell you that in general, environmental testing at the spacecraft development system level reveals problems that need to be corrected, which would take more time and money.”
Canceling VIPER will now save NASA at least $84 million. That could increase, he said, if VIPER’s launch goes beyond November 2025, which would require a 9- to 12-month wait before proper light conditions return at the polar landing site.
Kearns and Fox said that much of the science VIPER would perform would be performed by other missions, including landers and orbiters. The mobility that VIPER would provide, however, may not be available until NASA’s Lunar Terrain Vehicle, a manned rover for Artemis missions that can also be teleoperated, is delivered later this decade.
NASA plans to dismantle VIPER to reuse its instruments and other components. But first, NASA will consider proposals from US companies and international partners to fly VIPER independently at no cost to the government. Proposals are due to be submitted to NASA on August 1.
Review of Griffin’s mission
Regardless of its own development issues, VIPER faced delays to Griffin, Astrobotic’s lander that was supposed to carry the rover to the Moon under a $322 million CLPS contract. NASA said Griffin is now expected to be ready for a mission by September 2025 at the earliest.
After VIPER is canceled, NASA will retain the mission for Griffin. The mission will instead become a technology demonstrator, carrying a mass simulator in place of the rover to test Griffin’s ability to land large payloads.
Kearns said NASA considered flying science payloads instead, but because the lander was designed to carry the rover, it lacked the payload customization and capabilities such as power and communications that the payload would need.
“We believe that if we asked Astrobotic to make such changes, it would further delay their schedule,” he said of potential modifications to accommodate the payload. “It would lead to higher costs for the government. This would delay the demonstration of a successful landing at the South Pole by the large Griffin lander, which we are very interested in.
Astrobotic will also be free to fly its own commercial cargo. Astrobotic CEO John Thornton said in an interview that the company is considering testing its LunaGrid power generation service on Griffin. “We want to fly fast, but we also want to do a mission that will have a bigger impact than just the lander itself.”
Griffin without VIPER would still land in the moon’s south polar region, he said, though not necessarily in the same spot NASA chose for VIPER. It will depend on any new payloads it registers for the lander, with the option to move to a safer landing site to reduce risk to the mission.
Both Kearns and Thornton said the agency informed the company of the decision very recently, but were not more specific. One industry source said NASA informed Astrobotic of the decision just a day before it was publicly announced.
“It’s certainly been a tumultuous and challenging year for Astrobotic as a company,” he said, referring to the January launch of its first lunar lander, Peregrine, which suffered a fuel leak after launch and was unable to attempt a landing on the moon. . Canceling VIPER is “definitely another gut punch, but we’ll deal with it.”
Kearns said NASA believed Griffin would be able to land safely on the moon, with or without VIPER on board, and noted that NASA funded the company to conduct additional tests of the propulsion system. “We have faith in them to come out and attempt this landing, or we will not continue to work with them.”
“I’m an eternal optimist. One has to be in the space industry,” Thornton said. “I’m excited about what we can turn this into.”