CAPSTONE enters lunar orbit

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ORLANDO — A NASA-funded cubesat successfully completed a maneuver to enter orbit around the moon Nov. 13.

NASA announced that the Cislunar Autonomous Positioning System Technology Operations and Navigation Experiment (CAPSTONE) spacecraft, a 12U cubesat, completed a 16-minute maneuver at 7:39 p.m. Eastern, placing the spacecraft into a near-rectilinear halo orbit (NRHO) around the moon. Data from the spacecraft showed that the maneuver took place as expected.

“That is a huge step for the agency,” Jim Free, NASA associate administrator for exploration systems development, said at a Nov. 13 briefing about preparations for the Artemis 1 launch.

CAPSTONE is designed to test the stability of the NRHO, the orbit that NASA plans to use for the lunar Gateway. The spacecraft, operated by Colorado-based Advanced Space, will also test autonomous positioning technologies through a link to NASA’s Lunar Reconnaissance Orbiter.

“This is a very important orbit for us here on the Artemis program, specifically, because that is where we will fly Gateway,” Free said. “As CAPSTONE flies in that orbit for about six months, we’ll get more data to understand and characterize that orbit.”

CAPSTONE is the first spacecraft to fly in the NRHO, an elliptical orbit over the moon’s poles at altitudes ranging from 3,500 to 71,000 kilometers. It is also the first cubesat to go into any orbit around the moon.

CAPSTONE launched on a Rocket Lab Electron rocket June 28 and, after a series of maneuvers by Rocket Lab’s Lunar Photon kick stage, was deployed onto a low-energy ballistic lunar trajectory July 4. That trajectory took the spacecraft far beyond the moon before swinging back to allow it to enter orbit with a small maneuver.

CAPSTONE’s cruise was not without incident. The spacecraft lost communication with Earth shortly after deployment because of a glitch during commissioning, but contact was restored about a day later. The spacecraft went into safe mode during a trajectory correction maneuver in September, which engineers later traced to a valve problem with one of its thrusters. Controllers restored CAPSTONE to normal operations a month later.

While the orbital insertion maneuver was successful, NASA said that two “clean up” maneuvers are scheduled for this week. After that, NASA and Advanced Space will be able to confirm that CAPSTONE is in the desired orbit. CAPSTONE, with a total cost to NASA of about $30 million, has a six-month primary mission but the potential to operate for an additional 12 or more months in an extended mission.

While CAPSTONE is the first cubesat to orbit the moon, it may soon be joined by several others. The Artemis 1 mission, scheduled to launch as soon as Nov. 16, carries 10 cubesats, some of which will fly by, orbit, or land on the moon. Another NASA cubesat, Lunar Flashlight, is slated to launch to the moon later this month as a secondary payload on the launch of a commercial lunar lander by Japanese company ispace.

Advanced Space is now working on a second cislunar smallsat mission. The Air Force Research Lab awarded the company a $72 million contract Nov. 10 to build Oracle, a mission to test space situational awareness technologies beyond Earth orbit out to the moon. Oracle is scheduled to launch in late 2025 for a two-year mission.