A “microwave-sized” satellite is on its way to the moon after Rocket Lab successfully launched it out of the Earth’s atmosphere early Tuesday, the firm announced.

The Cislunar Autonomous Positioning System Technology Operations and Navigation Experiment, or CAPSTONE, satellite took off from Rocket Lab’s Launch Complex 1 in Mahia, New Zealand at 2:55 a.m. Long Beach time.

“Today’s launch was an important step in humanity’s return to the Moon and a testament to the determination, resolve, and innovation of the hundreds of people behind CAPSTONE,” Rocket Lab founder and CEO Peter Beck said in a statement.

The CAPSTONE satellite was designed and built by Tyvak Nano-Satellite Systems, a Terran Orbital Corporation, and owned and operated by Advanced Space on behalf of NASA.

The CubeSat was blasted into space aboard a Rocket Lab Electron rocket, marking the 27th launch of the vehicle following a successful mission less than two months ago.

The satellite is now in a stable, low-Earth orbit attached to one of the Rocket Lab’s Photon Lunar spacecraft buses, which will make a series of orbit-altering maneuvers over the next five days.

The Photon’s HyperCurie engine will then ignite periodically, increasing the craft’s velocity and stretching its orbit into prominent ellipses. Upon the final engine burn, Photon will reach speeds of about 24,500 mph before releasing CAPSTONE into space for its journey to the moon.

Rocket Lab engineers integrate the CAPSTONE CubeSat to a spacecraft ahead of a NASA lunar mission. Photo courtesy of Rocket Lab.

CAPSTONE will travel 963,000 miles—more than three times the distance between the Earth and moon—before the sun’s gravity pulls it back toward the Earth-moon system. The satellite is expected to settle into a Near Rectilinear Halo Orbit around the moon four months after departing Earth’s orbit.

If it successfully reaches its target, the NASA experiment will be the first spacecraft to test that particular orbit around the moon. The mission will test prediction models’ estimated propulsion requirements to maintain this particular orbit.

Data from CAPSTONE will inform future missions, including NASA’s Gateway program—a small, human-tended space station that will orbit the moon and provide extensive support for NASA’s Artemis campaign.

Artemis is expected to land the first woman and person of color on the moon as part of establishing a long-term presence on the Earth’s only natural satellite.

“Rocket Lab was founded to open access to space and enable ground-breaking missions like this that push the limits of what’s possible with small satellites,” Beck stated. “While CAPSTONE’s journey to the Moon has only just begun, we’re proud to have safely delivered [it] to space.”

Starting in about one week, people can follow CAPSTONE’s journey in real time using NASA’s Eyes on the Solar System interactive 3D data visualization.