CAPSTONE on target to reach lunar orbit after difficult journey

NASA’s CAPSTONE performed its fourth of six planned orbit correction maneuvers on Thursday, Oct. 27, paving the way for the spacecraft to arrive in an elliptical halo orbit in less than two weeks.

The 55-pound cube fired its propulsion system for 220 seconds during the planned maneuver, Advanced Space, the private company that manages the mission for NASA, explained in a update. The mission’s fourth orbit correction maneuver occurred late last week, pushing CAPSTONE ever closer to its final destination: the moon Near Rectilinear Halo Orbit (NRHO). The probe is expected to enter operational orbit on November 13.

Advanced Space says the probe was 308,076 miles (495,800 kilometers) from Earth at the time of the maneuver, or about 69,000 miles (111,000 km) beyond the moon. NASA and its partners use the ballistic moon transfer (BLT) technique to transfer CAPSTONE to NRHO, which, while complicated and long, is very economical. The spacecraft launched on June 28 and has flown solo in space for the past four months.

Once in NRHO, the $33 million cubes will enter uncharted territory, as no spacecraft has ever operated in this highly elliptical orbit — one intended for the coming gate space station. CAPSTONE, short for Cislunar Autonomous Positioning System Technology Operations and Navigation Experiment, will test this orbit for NASA and pave the way for Gateway and the upcoming Artemis Missions to the moon.

More about this story: This tiny moon-bound satellite could pave a path for a lunar space station

The latest trajectory correction maneuver “confirms preparation, comprehensive analysis, teams working together and hard to keep this mission successful, especially after the recent anomaly,” Alec Forsman, CAPSTONE mission operations manager at Advanced Space, said in the update.

Indeed, the mission threatened to go sideways after the third course correction maneuver on September 8, CAPSTONE, built by Terran Orbital, lost control of the shaft and began to tumble, a serious situation that threatened to derail the entire mission. CAPSTONE could not point its solar panels at the sun and could not fully charge.

The recovery team eventually traced the problem to a partially open valve on one of the spacecraft’s eight thrusters, which the team launched with a recovery order sent to CAPSTONE a full month after the anomaly. As NASA adds: “The mission team will design future maneuvers to work around the affected valve, including the two remaining orbit correction maneuvers planned for CAPSTONE’s arrival in lunar orbit.”

With the fourth orbit correction maneuver completed, CAPSTONE is now several days away from reaching its lunar orbit and entering the demonstration phase of the mission. The probe will spend at least six months collecting operational data and testing autonomous spacecraft-to-spacecraft navigation capabilities, the latter of which could eventually lead to spacecraft being able to determine their own locations in space without assistance from outside. An early successful test, in which NASA’s Deep Space Network enabled a conversation between CAPSTONE and the agency’s Lunar Reconnaissance Orbiter, is a promising start to the Cislunar Autonomous Positioning System demonstration, as Advanced Space calls it.

More: NASA tries to make manned moon landing during fourth Artemis mission