Two months ago, NASA cancelled VIPER, a science rover mission to the moon’s south pole to explore for water ice. This decision was made despite the fact that the rover is fully built and has completed final testing. As professional lunar scientists and engineers unaffiliated with VIPER, we maintain that the cancellation is a mistake. It indicates that NASA is not serious about sustainable space exploration through Artemis, its return to the moon program, and that the United States is willing to let China become the world leaders in lunar science, exploration and resources.
NASA states that “the pillars of science, national posture, and inspiration form the foundation of the agency’s exploration plans.” The VIPER cancellation directly undermines all three. It signals to the ever-growing lunar community that science is not important under Artemis. It allows other countries to continue to establish the standard for how the moon is to be explored. And it eliminates real time video of the first ever long-lived U.S. rover in operation on the moon that could inspire countless students and the public.
China is able, and willing, to fill this void. The Chang’e-7 and 8 missions will explore the lunar south pole for water ice in 2026 and 2028, respectively. This comes just after China returned the first ever samples from the far side of the moon. The last time the United States returned lunar samples was over 50 years ago. As China has publicly stated, the data from these missions will be used to inform where to build the Chinese-led International Lunar Research Station to make optimal use of lunar resources. Will they get the best location? More importantly, will they set the precedent for extracting and using lunar resources?
Apollo proved that exploration enables science. VIPER, for the first time on the moon, proves that science can enable exploration. VIPER will deliver critical science results about lunar water ice while at the same time validating how future exploration missions could “live off the land” using local resources. According to NASA’s own website, “VIPER’s findings will inform future landing sites under Artemis by helping to determine locations where water and other resources can be harvested to support a long-term presence on the moon.” NASA has yet to explain how this data void will be filled.
So why was VIPER canceled? VIPER’s original ride to the moon, provided by Astrobotic, is delayed by at least a year, while NASA’s delivery of VIPER to Astrobotic was delayed as well. This means NASA must spend more to keep the rover in ready-to-launch condition until the ride materializes. NASA did not plan for this cost growth, so when Congress cut NASA’s budget $525 million in 2024, NASA decided VIPER was less important than other science missions. What is especially disheartening is that construction of VIPER and environmental testing are complete! The cost savings now is minimal. As such, the House Committee on Science, Space, and Technology has rightfully requested NASA to provide further justification.
Due to overwhelming reaction from the community, NASA has half-heartedly thrown VIPER a life line. The resultant RFI, however, mandates a chosen partner must “openly disseminate science data” collected on the mission. In other words: fly this mission and deliver the data and products back to NASA for free. Companies will have to negotiate these barriers to close the business case. As a recent report suggests, ownership of the data from the mission is vital.
Many questions remain. Will NASA consider working with international partners if a United States company cannot afford to keep it going? Could partners who have already landed on the moon (such as Japan or India) be encouraged to fly VIPER? Is NASA pursuing the alternate approach for VIPER in good faith or seeking to temporarily placate an outraged community?
Most importantly, is NASA committed to collaborating “with commercial and international partners [to] establish the first long-term presence on the moon?” That is the stated purpose of Artemis, according to NASA. If the U.S. is serious about its leadership at the moon, staying true to its ideals of science, and committing to solving hard problems, we should finish what we started, with VIPER building a vibrant space exploration program that forms partnerships and expands our economy.
Clive R. Neal is a professor of lunar exploration at University of Notre Dame.
Ryan Whitley is the former Director of Civil Space Policy at the National Space Council.
Daniel Britt is the University of Central Florida Pegasus Professor of Planetary Exploration and Director of the Center for Lunar and Asteroid Surface Science.
Philip Metzger is the Director of the Stephen W. Hawking Center for Microgravity Research and Education at the University of Central Florida.
Editor’s note: This article has been updated to include more context about the factors that delayed VIPER.
