CAPSTONE Makes First Course Change

NASA’s CAPSTONE lunar cubesat successfully executed its first course change today after a communications glitch was resolved. The tiny spacecraft is taking a unique Ballstic Lunar Transfer trajectory to the Moon and will not arrive until November 13. At the moment, all is well.

Communications were lost with the Cislunar Autonomous Positioning System Technology Operations and Navigation Experiment (CAPSTONE) shortly after it separated from Rocket Lab’s Lunar Photon upper stage. The 55-pound satellite, the size of a microwave oven, talks to Earth via NASA’s Deep Space Network of antennas in  California, Spain and Australia. The first contact through Spain was fine, but abruptly stopped during a second session with a dish in California.

The situation was resolved yesterday and the first course change began at 11:30 am EDT today, lasting about 11 minutes.

CAPSTONE is owned and operated for NASA by Advanced Space of Westminster, CO.  The two issued statements today explaining what went wrong. The DSN team noticed inconsistent ranging data so the spacecraft operations team tried to access data on the spacecraft’s radio. They sent an improperly formatted command that “triggered a radio vulnerability.”  Fault detection software should have turned it back on, but didn’t because of a software error.  Eventually other software on the spacecraft cleared the fault and the radio came back online.

Everything appears fine now. The next trajectory change is scheduled for July 9.

CAPSTONE is on its way to a Near Rectilinear Halo Orbit around the Moon that will bring it as close as 1,000 miles of one lunar pole but 43,500 miles from the other every seven days. No spacecraft has been there before. NASA plans to put a small space station there called Gateway to support the Artemis program. CAPSTONE will validate NASA’s models of requirements for power and propulsion to maintain the orbit and test navigation capabilities using NASA’s Lunar Reconnaissance Orbiter as a reference point. LRO has been orbiting the Moon since 2009 taking detailed images of the surface.

CAPSTONE was launched on Rocket Lab’s Electron rocket from New Zealand. It is the first use of the Lunar Photon upper stage, which Rocket Lab plans to use for other deep space missions.

The project is part of NASA’s Small Business Innovation Research (SBIR) program under the Space Technology Mission Directorate. Advanced Space received a $13.7 million contract to develop and manage the spacecraft. Rocket Lab’s launch cost $9.95 million.

A large team was responsible for building and launching this tiny satellite. Advanced Space lists these “critical partners”:

• NASA: CAPSTONE’s development is supported by the Space Technology Mission Directorate via the Small Spacecraft Technology and Small Business Innovation Research programs at NASA’s Ames Research Center. The Artemis Campaign Development Division within NASA’s Exploration Systems Development Mission Directorate supports the launch and mission operations. NASA’s Launch Services Program at Kennedy Space Center is responsible for launch management. NASA’s Jet Propulsion Laboratory supported the communication, tracking, and telemetry downlink via NASA’s Deep Space Network, Iris radio design, and groundbreaking 1-way navigation algorithms.
• Terran Orbital Corporation: Design and built spacecraft.
• Stellar Exploration: Propulsion subsystem provider.
• Rocket Lab USA, Inc.: Launch provider
• Space Dynamics Lab (SDL): Iris radio and navigation firmware provider.
• Orion Space Solutions (formerly Astra): Chip Scale Atomic Clock (CSAC) hardware provider for the 1-way ranging experiment.
• Tethers Unlimited, Inc.: Cross Link radio provider.
• Morehead State University (MSU): Provides telemetry, tracking and control services via NASA’s Deep Space Network (DSN ).