The first cube to fly and operate on the moon has successfully arrived

After a nearly five-month journey that took it beyond the moon and back, the CAPSTONE small spacecraft has successfully entered lunar orbit.

“We have received confirmation that CAPSTONE has reached a near-straight halo orbit, and this is a huge and huge step for the agency,” said Jim Frye, NASA’s chief of development for exploration systems. “It just completed its first burn a few minutes ago. Over the next few days, they will continue to improve its orbit, and they will be the first cube to fly and operate on the Moon.”

This is an important orbit for NASA, and a special one, because it’s really stable, and only requires a tiny amount of fuel to stabilize it. At its closest to the Moon, this almost week-long orbit passes 3,000 km from the surface of the Moon, and at other points it is 70,000 km away. NASA plans to build a small space station, called Moon Gate, here later this decade.

But before that, the agency started small. CAPSTONE is a rogue commercial mission that was supported financially, in part, by a $13.7 million grant from NASA. The spacecraft itself was developed by a Colorado-based company called Advanced Space, with the help of Terran Orbital, and is of modest size, only 12U cubes with a mass of about 25 kg. It can be conveniently placed inside a small refrigerator.

The spacecraft was launched at the end of June on an Electron rocket from New Zealand. The Electron is the smallest rocket to launch a payload on the Moon, and its manufacturer, Rocket Lab, has stressed the capabilities of the booster and its upper photon stage to the max to send CAPSTONE on its long journey to the Moon. This was the first mission of the Rocket Lab into deep space.

After separating from its rocket, the spacecraft spent nearly five months traveling to the Moon, following what is known as a ballistic transfer to the Moon that uses the Sun’s gravity to follow an extended path. Along the way, flight controllers managed this Spinning problem solving That could have led to the loss of the spacecraft. This was a circular path, causing the spacecraft to reach a distance of more than three times the distance between Earth and the Moon before turning back, but requiring relatively little propellant to reach its destination.

For example, the burn that CAPSTONE carried out on Sunday evening to move into a near-straight-line halo orbit was very small. According to Advanced Spacethe craft burned its thruster for 16 minutes at about 0.44 newtons, which is the weight of about nine pieces of standard printer paper.

CAPSTONE will not only serve as a motor in this new orbit – to verify theoretical properties designed by NASA engineers – but will also demonstrate a new autonomous navigation system around and near the Moon. This Autonomous Cislunar Positioning System, or CAPS, is important because there is a shortage of fixed tracking assets near the Moon, especially as the cislunar environment becomes more crowded over the next decade.

The mission is scheduled to operate for at least six months in this orbit.