Dubbed the near-straight line halo orbit, the orbit is very elongated, providing stability for long-term missions while requiring little power to maintain – just what the Gateway needs. The orbit exists at a balanced point in the gravity of the moon and earth.
Dubbed the Cislunar Autonomous Positioning System Technology Operations and Navigation Experiment and known as CAPSTONE, the mission is scheduled to lift off from the launch pad at 6 a.m. ET on Monday, June 27. The CubeSat will be launched aboard Rocket Lab’s Electron rocket from the company’s Launch Complex 1 in New Zealand.
After CAPSTONE’s launch, it will reach the orbit point within three months and then spend the next six months in orbit. The spacecraft can provide more data on the power and propulsion requirements for the gateway.
CubeSat’s orbit will put the spacecraft within 1,609.3 kilometers (1,000 miles) of a lunar pole when it passes closest every seven days, and within 70,006.5 kilometers (43,500 miles) of the other pole. Using this orbit will be more energy efficient for spacecraft flying to and from the Gateway, as it requires less propulsion than more circular orbits.
The miniature spacecraft will also be used to test communications capabilities with Earth from this orbit, which offers the benefit of a clear view of Earth while providing coverage for the moon’s south pole – where the first Artemis astronauts are expected to land will be 2025 .
NASA’s Lunar Reconnaissance Orbit, which has been circling the Moon for 13 years, will provide a reference point for CAPSTONE. The two spacecraft will communicate directly with each other, allowing teams on the ground to measure the distance between them and pinpoint CAPSTONE’s precise location.
Cooperation between the two spacecraft can test CAPSTONE’s autonomous navigation software called CAPS or the Cislunar Autonomous Positioning System. If this software works as expected, future spacecraft could use it without relying on tracking from Earth.
“The CAPSTONE mission is a valuable precursor not only to Gateway, but also to the Orion spacecraft and the human landing system,” said Nujoud Merancy, director of NASA’s Exploration Missions Planning Office at the Johnson Space Center in Houston. “Gateway and Orion will use the data from CAPSTONE to validate our model, which will be important for future mission operations and planning.”
Small satellites on big missions
The CAPSTONE mission is a rapid, low-cost demonstration designed to help lay a foundation for future small spacecraft, said Christopher Baker, director of the small spacecraft technology program at NASA’s Space Technology Mission Directorate.
Small missions that can be assembled and launched quickly at a lower cost mean they can take risks that larger, more expensive missions cannot.
“So often in a flight test, you learn just as much, if not more, from failures than you do from successes. We can afford to take more risks, knowing that there is a chance of failure, but that we can take that failure in turn and move into more advanced skills,” Baker said. “In this case, failure is an option .”
Lessons learned from smaller CubeSat missions can later inform larger missions – and CubeSats have already made their way to more challenging targets than low Earth orbit.
During InSight’s entry, descent, and landing, the MarCO satellites received and transmitted communications from the lander to notify NASA that InSight was safely on the red planet’s surface. They were nicknamed EVE and WALL-E, after the robots from the 2008 Pixar film.
The fact that the tiny satellites made it to Mars and flew through space behind InSight delighted engineers. The CubeSats continued to fly beyond Mars after InSight landed, but fell silent by the end of the year. But MarCO was an excellent test of how CubeSats can compete on larger missions.
These tiny but powerful spacecraft will again play a supporting role in September when the DART mission, or Double Asteroid Redirection Test, will intentionally crash into the moon Dimorphos as it orbits the near-Earth asteroid Didymos to record the asteroid’s movement in space change .
The CAPSTONE mission relies on NASA’s partnership with commercial companies such as Rocket Lab, Stellar Exploration, Terran Orbital Corporation and Advanced Space. The lunar mission was built through an innovative small business research contract at a fixed price – in less than three years and for less than $30 million.
Larger missions can cost billions of dollars. The Perseverance rover, currently exploring Mars, costs more than $2 billion, and the Artemis I mission has an estimated cost of $4.1 billion, according to a NASA Inspector General review.
These types of contracts can expand opportunities for small, more affordable missions to the moon and other destinations, while providing a framework for commercial support for future lunar operations, Baker said.
Baker hopes small spacecraft missions can increase the pace of space exploration and scientific discovery – and CAPSTONE and other CubeSats are just the beginning.
Correction: A previous version of this story had an incorrect start date.