WASHINGTON — A year after its launch, a privately owned, NASA-funded cubesat orbiting the moon continues to work well, providing data to support the agency’s Artemis lunar exploration efforts.
The Cislunar Autonomous Positioning System Technology Operations and Navigation Experiment (CAPSTONE) spacecraft, owned by Colorado startup Advanced Space, started its journey to the moon last July after its launch on a Rocket Lab Electron rocket. After overcoming communications and thruster problems, the spacecraft entered a near-rectilinear halo orbit (NRHO) around the moon in November.
CAPSTONE has completed a six-month primary mission in that orbit and is now in an “enhanced” mission slated to last at least a year. “For us, the enhanced mission really just gets into focusing in on some more of the automation experiments and trying to collect more data,” Brad Cheetham, chief executive of Advanced Space, said in an interview. “We can try some new things. We can push the envelope.”
The spacecraft has been working well, with only minor technical issues, since reaching the moon. “We got through a lot of challenges to get to the moon,” he said. “Once we got there, we settled into an operational cadence, which really helped inform a lot of the analysis that’s being done by the Gateway team at the Johnson Space Center and others to learn how to operate there.”
NASA funded development of CAPSTONE to test the stability of NRHO, which will be used by the lunar Gateway that the agency and international partners will develop over the course of several Artemis missions. That’s included insights on how to conduct stationkeeping maneuvers to maintain the orbit and how to perform navigation.
Cheetham described as “phenomenal” his company’s relationship with NASA’s Gateway program, which predates development of CAPSTONE. “The teamwork between analysis for Gateway and planning for CAPSTONE has been almost seamless,” he said, with an exchange of information that has both supported planning for Gateway and operations of CAPSTONE. “That back and forth has been like it’s almost one team.”
Advanced Space has also used CAPSTONE to test autonomous navigation technologies. After several attempts, the spacecraft established a crosslink with the Lunar Reconnaissance Orbiter, testing the “CAPS” part of the mission’s name. They have also used a chip-scale atomic clock on the cubesat to determine its location using timing information from signals uplinked to it from ground stations.
The experience from CAPSTONE will help Advanced Space on its next spacecraft mission called Oracle for the Air Force Research Laboratory. The company won a $72 million contract from AFRL in November 2022 to develop a smallsat, previously known as the Cislunar Highway Patrol System, to monitor cislunar space and demonstrate positioning and navigation techniques beyond Earth orbit.
“We know what these systems can do and where they might have problems,” he said, allowing the company to focus on novel aspects of the mission. “We’ll really be able to put our attention on the new things that are different from CAPSTONE or the things that are potentially harder.”
Advanced Space, besides operating CAPSTONE and developing Oracle, recently announced it is supporting ESCAPADE, a NASA smallsat mission to study the interaction of Mars with the solar wind, with mission design and navigation. It is also part of a team led by Draper that won a NASA Commercial Lunar Payload Services award to land a spacecraft on the far side of the moon.
CAPSTONE, meanwhile, may operate well beyond the one-year enhanced mission. Cheetham said the main concern is the effects of radiation on the spacecraft’s electronics, particularly as the sun approaches the peak of its 11-year activity cycle. Fault protection systems on the cubesat have recovered it from several radiation-induced upsets so far, but it’s uncertain how much of a total dose those systems can receive before they degrade.
Propellant, he added, is not a concern. “We have plenty of delta-V margin and gotten efficient on how to deploy it,” he said. “As a mission led and managed by orbital mechanics, we have plenty of fuel. We will not run out of fuel on the program.”