NASA prepares long duration Antarctic balloon campaign to probe neutrinos and dark matter

by Clarence Oxford
Los Angeles CA (SPX) Dec 05, 2025

NASA's Scientific Balloon Program is returning to Antarctica for a new long-duration campaign featuring two zero-pressure balloon launches from a site near the U.S. National Science Foundation's McMurdo Station on the Ross Ice Shelf. The flights will carry the Payload for Ultrahigh Energy Observations (PUEO) and the General AntiParticle Spectrometer (GAPS), both focused on high-energy astrophysics.

The PUEO mission is the first balloon-borne project selected under NASA's Astrophysics Pioneers program, which supports astrophysics investigations at lower cost. PUEO is designed to detect radio signals produced when ultra-high energy neutrinos from distant cosmic events interact with Antarctic ice, using the ice itself as a large detection medium. The survey aims to improve sensitivity to cosmic ultra-high energy neutrinos and provide new data on extreme astrophysical processes such as black hole formation and neutron star mergers.

Acting Astrophysics Division director Shawn Domagal-Goldman described the mission as using Antarctica's ice as a single, large telescope to capture signals from high-energy events and noted that the program structure supports early- and mid-career researchers by enabling different, lower-cost approaches to astrophysics missions. The PUEO payload will fly beneath a scientific balloon, using antennas and associated instruments to search for the brief radio flashes triggered when neutrinos strike the ice. Integration work for the payload in Antarctica includes mechanical positioning, attachment of solar power systems, and configuration of communications and pointing hardware prior to launch.

The GAPS experiment will investigate the nature and origin of dark matter, which accounts for more than 80 percent of the universe's matter content but has not yet been directly identified. GAPS is optimized to detect specific antiparticles that can be produced when dark matter particles decay, and a single confirmed detection of such a particle would significantly advance understanding of dark matter and large-scale cosmic structure. Flying on a long-duration balloon over Antarctica allows GAPS to operate in a stable environment at high altitude, above much of Earth's atmosphere, increasing sensitivity to these rare antiparticle signals.

Zero-pressure balloons used in the campaign are engineered to stay in pressure balance with the surrounding atmosphere by venting gas through ducts as they ascend, preventing internal pressure buildup. Their design, combined with polar circulation patterns and continuous sunlight during the Antarctic summer, supports extended flights that can remain aloft for long periods while carrying heavy scientific payloads. NASA's Wallops Flight Facility manages the scientific balloon program, with Peraton operating the Columbia Scientific Balloon Facility in Texas to provide mission planning, engineering, and field operations, while Aerostar fabricates the balloons for these missions.