FROM ORBIT VALIDATION TO OPERATIONAL REHEARSAL

NASA has announced a new technology demonstration mission at the Moon under a contract awarded to Advanced Space. The CAPSTONE 02 mission, targeted for launch in 2027, will use two small spacecraft in lunar orbit to demonstrate rendezvous and proximity operations, autonomous navigation and cislunar communication capabilities, while continuing to characterise the radiation environment at the Moon. The mission forms part of NASA’s work with industry to advance the next phase of cislunar infrastructure for the Artemis programme and Moon Base, including orbital assets and demonstrations.

The original CAPSTONE mission — Cislunar Autonomous Positioning System Technology Operations and Navigation Experiment — became the first US commercial mission to the Moon and the first spacecraft to operate in a near rectilinear halo orbit, a nearly stable trajectory maintained by the interacting gravitational pull of both Earth and Moon. That mission validated communications, networking and autonomous navigation capabilities while gathering operational experience in cislunar space. CAPSTONE 02 expands on those results by transitioning from orbit validation to operational demonstrations intended to inform future lunar exploration and infrastructure development.

WHY RENDEZVOUS IN CISLUNAR SPACE IS A HARDER PROBLEM

The core technical objective is relative navigation for rendezvous and proximity operations in cislunar space — techniques NASA describes as more sophisticated than their low Earth orbit equivalents, and which are designed to support astronauts docking with Moon landers in cislunar orbit to enable safe crew transfers to and from the lunar surface. The additional difficulty arises from the three-body dynamics of the region: spacecraft trajectories are governed by the simultaneous gravitational influence of both Earth and Moon rather than by a single dominant body, producing motion that cannot be modelled with the same techniques that serve reliably in Earth orbit.

The mission will fly two identical spacecraft of approximately 400 kilograms (882 pounds) supplied by Terran Orbital Systems. Mission operators will conduct a series of rendezvous, proximity operations and loitering — or formation flying — manoeuvres in lunar orbit with each spacecraft, to better understand trajectory behaviour under three-body conditions. Navigation will draw on ground tracking measurements, optical sensors and celestial bodies to help one spacecraft locate and rendezvous with the other, applying strategies similar to those planned for Orion’s approach to a lunar lander in deep space. Each spacecraft will be able to switch between ‘chaser’ and ‘target’ roles, allowing a broad range of operational scenarios to be tested under varying environmental conditions.

SOFTWARE TESTBED AND AUTONOMOUS NAVIGATION MATURATION

CAPSTONE 02 will also serve as an operational testbed for three NASA-developed navigation software suites, each collecting data during the spacecraft’s low energy transfer trajectory — a route taking the vehicles from Earth to beyond the Moon before settling into lunar orbit. The spacecraft will carry an optical imaging payload from Lawrence Livermore National Laboratory to support the navigation demonstration and to capture imagery of the Moon. The mission will further mature the Cislunar Autonomous Positioning System navigation software first demonstrated on the original CAPSTONE, a method of determining spacecraft position relative to other spacecraft without relying on Earth-based tracking.

The strategic value of that capability is significant for sustained lunar operations. Earth-based tracking through the Deep Space Network is a finite, heavily contested resource, and a lunar infrastructure supporting regular crewed and cargo traffic cannot depend on it for routine navigation. The CAPSTONE 02 technology suite is designed to automate routine navigation tasks, reduce reliance on traditional space-to-ground data, and enable new mission concepts derived from increased inter-satellite coordination. The spacecraft are additionally designed for cost-effective, rapid deployment, demonstrating what NASA describes as a scalable and repeatable mission model.

PROGRAMME STRUCTURE AND MANAGEMENT

Christopher Baker, Lead of the InSpace Infrastructure portfolio within NASA’s Research and Technology Mission Directorate, said that achieving the agency’s most ambitious space exploration goals required iterative, risk-tolerant demonstrations in partnership with industry, and that technology development through flight testing was how hard problems were converted into the lasting capabilities needed for a permanent presence at the Moon. Sean Fuller, Moon Base CAPSTONE manager, said the mission represented an important step in the maturation of cislunar capabilities, and that by expanding on the lessons of the original CAPSTONE to demonstrate increasingly sophisticated operational concepts, CAPSTONE 02 laid the foundation for lunar infrastructure and commercial services supporting Artemis, Moon Base and future deep space missions.

The mission is funded by NASA’s Human Spaceflight Mission Directorate with support from the Research and Technology Mission Directorate, and is managed by Small Spacecraft and Distributed Systems, based at NASA’s Ames Research Center in California. NASA used a Small Business Innovation Research Phase III contract to fund the mission — a procurement route allowing an agency to award follow-on work to a small business whose technology emerged from earlier SBIR-funded research, and which in this case connects the original CAPSTONE demonstration directly to its operational successor.