NASA soon will test a circuitous route to the Moon that takes its microwave oven-sized CubeSat satellite nearly a million miles into deep space to take advantage of gravitational forces that will allow it to reach the Moon with less expenditure of energy, the space agency reports.
The route, called a “near rectilinear halo orbit” (NHRO) works well in NASA’s computer simulations. CAPSTONE, short for the Cislunar Autonomous Positioning System Technology Operations, will provide the first real-world test of NRHO dynamics. The mission is intended to support NASA’s Gateway, a multipurpose outpost that will support long-term lunar missions under the Artemis orbit.
While the gravity-driven track will longer to reach the Moon — four months — NASA says it will “dramatically reduce the amount of fuel this pathfinder CubeSat will need to fly there.”
CAPSTONE will be launched from a complex in New Zealand. After six days in Earth Orbit, a final ignition will accelerate the rocket to 24,500 miles per hour to escape low-Earth orbit on a trajectory into deep space. Assisted by the sun’s gravity, it will reach 963,000 miles from Earth, more than three times the distance between the Earth and the Moon, before being pulled back towards the Earth-Moon system.
“This sinuous track — called a ballistic lunar transfer, or BLT — follows dynamic gravitational contours in deep space,” NASA says. The CAPSTONE team will calculate the BLT trajectory based on ever-changing positions of Earth, Moon and Sun. Expending little energy, CAPSTONE will “cruise along these contours” punctuated by a series of planned trajectory correction maneuvers.
“While going 3,800 miles per hour, it will perform its delicate, precisely timed propulsive maneuver to enter orbit, like a flying trapeze artist who jumps from one arc to another with a decisive, acrobatic motion.” NASA says.
No spacecraft has ever been placed in this type of orbit before.