CAPSTONE Enters Unique NRHO Lunar Orbit

CAPSTONE became the first cubesat to enter lunar orbit last night. Developed through a Public-Private Partnership with NASA, the tiny Cislunar Autonomous Positioning System Technology Operations and Navigation Experiment is testing out a unique lunar orbit called a Near Rectilinear Halo Orbit or NRHO. The agency plans to put a small space station there as part of the Artemis program of sustained exploration and use of the Moon.

NASA confirmed that CAPSTONE entered the highly elliptical NRHO at 7:39 pm ET last night. Over the next five days, it will fire its engines twice more to refine the orbit.

The microwave-oven sized CAPSTONE spacecraft was developed through NASA’s Small Business Innovation Research (SBIR) program and is led by Advanced Space of Westminister, CO. NASA awarded Advanced Space a $13.7 million contract to develop and manage the spacecraft. It was designed and built by Tyvak Nano-Satellite Systems, a Terran Orbital Corporation. CAPSTONE is owned by Advanced Space on behalf of NASA and operated jointly by Terran Orbital and Advanced Space.

CAPSTONE was launched on June 28, 2022 on a Rocket Lab Electron launch vehicle. The launch cost $9.95 million. That makes the total cost of the mission just $23.65 million, an extremely modest sum for any spacecraft much less one headed to the Moon.

It ran into a few problems along the way, briefly losing communications with Earth during a course change in July, and losing stabilization after another trajectory correction in September. Operators were able to get it back under control a few weeks later, however, and it arrived at the Moon on schedule yesterday.

The NRHO is a highly elliptical orbit that will bring a spacecraft as close as 1,000 miles of one lunar pole, but 43,500 miles from the other every seven days.

NASA is focusing its lunar operations on the Moon’s South Pole where scientists believe water exists in the form of ice. The theory is that water deposited by comets over the eons remains there in Permanently Shadowed Regions never exposed to the Sun.

The agency is teaming with the private sector and three of its partners from the International Space Station — Europe, Canada, and Japan — to build the Gateway as a waypoint between the Earth and the Moon. Astronauts will travel to the Gateway on Orion spacecraft. Some will stay there while others transfer to lunar landers built and owned by the private sector for the journey down to and back from the surface. They’ll make the trip to the lunar South Pole at times when the NRHO orbit is close to the surface. But the orbit also allows access to many other parts of the Moon and continuous line-of-sight communications with Earth.

CAPSTONE will validate NASA’s models of requirements for power and propulsion to maintain the NRHO orbit and test navigation capabilities using another NASA satellite that’s been orbiting the Moon since 2009, the Lunar Reconnaissance Orbiter, as a reference point.

NASA Administrator Bill Nelson was among those tweeting his congratulations.

Big news! @NASA‘s #CAPSTONE arrived to its orbit at the Moon and completed its first orbit insertion maneuver!

The spacecraft will continue to refine its orbit over the next few days, and will test the orbit planned for the @NASA_Gateway lunar outpost. https://t.co/oy7Rhl2oPf

— Bill Nelson (@SenBillNelson) November 14, 2022

Terran Orbital Co-Founder, Chairman, and Chief Executive Officer Marc Bell said they “had the privilege of never experiencing a dull moment.” Engineers “continuously met rapidly changing circumstances with precision and innovation bolstered by the advantages of in-house hardware and software development. The design, modeling, and simulation concepts refined throughout the process will ensure the successful flights of countless future generations of spacecraft. Terran Orbital is grateful for the trust, support, and collaboration of NASA, Advanced Space, and Rocket Lab, and we look forward to fostering these partnerships in imminent collaborations.”

Advanced Space CEO and CAPSTONE Principal Investigator Bradley Cheetham called it “a major milestone not just for our organizations but for our industry.” The NASA-industry team “has demonstrated an entirely new approach to supporting space exploration.”

CAPSTONE was Rocket Lab’s first mission beyond Earth orbit using the Lunar Photon upper stage. The company tweeted its congratulations today along with a video of the June 28 launch from Rocket Lab’s Launch Complex 1 on New Zealand’s Mahia Peninsula.

Welcome to the Moon, CAPSTONE pic.twitter.com/atMF35y0tI

— Rocket Lab (@RocketLab) November 14, 2022

The spacecraft took a rather circuitous route to the Moon called a ballistic lunar transfer (BLT) that limits the amount of energy that must be expended, which is why the trip took almost five months.