Leonard David's INSIDE OUTER SPACE

CAPSTONE
Image credit: NASA

NASA’s Moon mission mouthful, the Cislunar Autonomous Positioning System Technology Operations and Navigation Experiment, is doing just fine.

Mercifully called CAPSTONE for short, the CubeSat has been operating in a Near Rectilinear Halo Orbit (NRHO) for 85 days – completing approximately 12.5 orbits since arrival November 13^th of last year.

The microwave oven–sized spacecraft, tipping the scales at a modest 55 pounds, is serving as the first spacecraft to test the unique, NRHO lunar orbit. Advanced Space of Westminster, Colorado owns and operates the spacecraft for the entirety of its mission.

The spacecraft has operated successfully through two lunar eclipses, Advanced Space explains, which present a challenge for the spacecraft thermal and power systems. Other notable events include the successful execution of 2 maintenance maneuvers to keep CAPSTONE in its desired orbit.

Dylan Schmidt, CAPSTONE assembly integration and test lead, right, and Lachlan Moore, systems integration engineer, left, install solar panels onto the CAPSTONE spacecraft at Tyvak Nano-Satellite Systems, Inc., in Irvine, California.

New cadence

According to Advanced Space, mission operators had originally planned to execute an orbital maintenance maneuver each revolution of the orbit. A new cadence has been selected to help reduce operational risk and complexity.

“This updated operational approach maintains the required orbit phasing for the mission and demonstrates the robustness of the design strategy for these maneuvers,” Advanced Space adds. This design strategy has been developed by the NASA team supporting the space agency’s cislunar Gateway mini-space station project at the Johnson Space Center.

NASA’s cis-lunar Gateway facility.
Image credit: NASA

Cross-link attempt

In other CAPSTONE updates, the mission team successfully completed interface testing with the NASA Lunar Reconnaissance Orbiter (LRO) ground systems.

During the first attempt to obtain cross-link measurements on January 18th, LRO received a signal from CAPSTONE. However, the CAPSTONE radio system did not collect crosslink ranging measurements from the returned signal.

This initial try using the Cislunar Autonomous Positioning System (CAPS) software is informing subsequent work that will be further evaluated on upcoming attempts.

Jeffrey Parker, chief technology officer of Advanced Space (left) explains the CAPSTONE mission to U.S. Senator John Hickenlooper over a full-size model of the spacecraft.
Image credit: Advanced Space/Jason Johnson

CAPSTONE recovered from an anomaly on January 26^th that resulted in the spacecraft being unable to receive commands from ground operators. This issue was cleared by the on-board fault protection system as designed on February 6th and the system has returned to normal operations.

“Lessons learned from this anomaly will result in operational procedure changes to speed recovery from any future similar anomalies,” Advanced Space reports.