NASA has successfully tested a navigation system that lets an aircraft identify hazardous terrain and change its landing approach, a capability being developed to help future spacecraft land safely on the Moon and Mars. The experiment used an Alta-X drone carrying NASA's Safe and Precise Landing – Integrated Capabilities Evolution (SPLICE) system, which performed simulated lunar descent and landing manoeuvres over Rogers Dry Lake near the agency's Armstrong Flight Research Center in Edwards, California, on 27 August. NASA announced the results on 4 November, saying the technology had demonstrated its ability to assess potential landing sites and guide a vehicle towards safer terrain.
SPLICE brings together navigation sensors, computers and guidance software designed to help a spacecraft determine where it is, identify obstacles and land accurately without relying entirely on instructions from Earth. Terrain-relative navigation uses a camera to photograph the surface and compare the images with maps previously obtained by orbiting spacecraft, while Navigation Doppler Lidar uses laser beams reflected from the surface to measure altitude and velocity, providing more precise measurements than conventional radar landing sensors while requiring less mass and power. Hazard Detection Lidar scans the terrain to produce a three-dimensional map, a descent and landing computer processes the sensor information to identify hazards and calculate a landing location, and adaptive guidance software can change the trajectory if the original site proves unsuitable. NASA says the hazard detection system is designed to begin scanning at an altitude of approximately 500 metres.
Development of SPLICE began in 2017, building on earlier NASA research into autonomous landing and hazard avoidance. The August demonstration followed several months of testing by engineers from NASA's Johnson Space Center in Houston and Armstrong Flight Research Center, with Johnson developing the payload and Armstrong integrating it with the Alta-X drone; initial flights in June and July examined communications, telemetry, data handling and command-and-control functions, and a 15 July flight saw the payload communicate with the remotely piloted drone during hovering manoeuvres. Earlier work included sensor flights aboard Project Morpheus in 2014, Masten Space Systems' Xodiac rocket in 2017 and 2019, a rocket sled test of Navigation Doppler Lidar at speeds approaching 480 mph in June 2019, helicopter testing in March 2025, and closed-loop drone testing at Voyager Technologies' Lunar Surface Proving Grounds in Mojave, California, in August 2026. NASA is working with commercial lunar lander companies to incorporate SPLICE technologies into future spacecraft, and project manager Davis Adams said the team is coordinating with industry on use of the guidance system once it is available in the NASA software catalog, currently planned for this fall. NASA's project records list September 2026 as the SPLICE project closeout milestone.