The small satellite has had a bumpy ride, but it is set to enter lunar orbit this weekend. While NASA prepares for the launch of its first large Artemis mission next week, a tiny CubeSat aims to reach the moon this weekend and act as a trailblazer for future stages of the Artemis programme.
Capstone, which stands for Cislunar Autonomous Positioning System Technology Operations and Navigation Experiment, is the size of a microwave oven and is meant to circle the moon in an eccentric elliptical orbit (officially termed as a near rectilinear halo orbit) never before flown by spacecraft.
Capstone is testing the route ahead of NASA’s plans to build the Gateway space station in the same orbit. The Gateway will serve as a stopping place for Artemis personnel, equipment, and supplies en route to the lunar surface.
The small satellite is scheduled to undertake its initial orbit insertion manoeuvre on Sunday at 4:18 p.m. PT. The spacecraft’s propulsion system will fire at precisely the right time while travelling at 3,800 miles per hour to enter the special orbital path, which will allow it to circle the moon along a very fuel-efficient route, relying instead on the moon’s and Earth’s gravitational pulls to stay on course.
It will take roughly a week for mission engineers to validate and fine-tune Capstone’s path following orbital insertion.
Capstone’s trip to the moon has been turbulent. The little craft lost contact with Earth in July and later experienced a catastrophic technological glitch that left it spinning out of control for a spell. The team was eventually able to orient it, get it under control, and get it back on track.
“What this Capstone team has accomplished to date has been extraordinary,” said Bradley Cheetham, Capstone’s principal investigator and the CEO of Advanced Space, in a statement. Advanced Space, based in Colorado, owns and operates Capstone for NASA.
“The goal of a pathfinding mission is to overcome hurdles,” Cheetham remarked.
Capstone is scheduled to use its thrusters only once every six and a half days after entering orbit, if necessary. The goal is to keep Gateway in orbit for at least six months so engineers can learn more about what it will take to keep Gateway and other spacecraft on such a trajectory for many years.