NASA’s CAPSTONE: Flying a New Path to the Moon

CAPSTONE is now on a ballistic lunar transfer trajectory to the Moon, a convoluted—but efficient—trajectory in which the probe will follow “dynamic gravitational contours in deep space,” as NASA explains:

Expending little energy, CAPSTONE will cruise along these contours punctuated by a series of planned trajectory correction maneuvers. At critical junctures, CAPSTONE’s team at Advanced Space’s mission operations center will command the spacecraft to fire its thrusters to adjust course. Terran Orbital Corporation in Irvine, California, designed and built CAPSTONE and developed novel technology that allows the spacecraft to execute maneuvers while maintaining control of the spacecraft on thrusters only.

When CAPSTONE catches up to the Moon, its approach will be perfectly aligned for NRHO insertion, the crux of its route. While going 3,800 miles per hour [6,116 km/hr], 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.


NRHO represents an ideal gravitational sweet spot for Lunar Gateway. Here, the pull of gravity from the Earth and Moon interact to enable a near-stable orbit, “allowing physics to do most of the work of keeping it in orbit around the Moon,” according to NASA. CAPSTONE will spend six months in NRHO, during which time it will travel to within 2,100 miles (3,400 km) of the Moon’s north pole on its near pass and 47,000 miles (76,000 km) from the south pole at its most distant.

In addition, CAPSTONE will test a navigational system in which the probe will measure its location relative to NASA’s Lunar Reconnaissance Orbiter and without the benefit of ground stations on Earth.


More: Astronauts Can Suffer a Decade of Bone Loss During Months in Space.