By Sarah Cope | 2026-05-14

South Africa supported NASA's successful Artemis II mission through ground-based tracking and communications, marking a significant expansion in its participation in international space exploration efforts.

Artemis II carried four astronauts around the moon in a historic April voyage that brought humans the closest they have been to the moon in 50 years and the farthest they have ever been from Earth.

During that endeavor, maintaining continuous contact between the spacecraft and ground systems was essential.

Through the South African National Space Agency (SANSA), the country provided telemetry, tracking, and command support for the Orion spacecraft as it traveled beyond low Earth orbit.

This support was centered at the Hartebeesthoek Radio Astronomy Observatory in Gauteng province, established in 1961, which is integrated into NASA’s global communications network.

Different missions use different frequency bands — Sband, Xband, Ku or Ka — and the antennas must match those requirements.

The observatory used a 12-meter dish built in 1963 and a backup LSX antenna installed in 1988 to provide one-way Doppler or telemetry data, SANSA's executive director for space operations Raoul Hodges told Biz News on April 11.

"This allows us to measure where the spacecraft is," he told the outlet. "Using the antenna's angles and signal timing, we determine how far away the capsule is and how fast it’s moving."

"By combining data from three stations, you get an accurate position of the spacecraft."

The observatory's strategic location in the southern hemisphere enabled it to maintain contact with the spacecraft when stations in other parts of the world were out of range due to Earth’s rotation.

SANSA's critical role

Spaceflight depends on a network of ground stations distributed around the world, forming a continuous communication chain, Kenya-based news and consultancy platform Africa Sustainability Matters (ASM) explained April 15.

"Each station assumes responsibility for tracking and data transmission when the spacecraft enters its coverage area, ensuring that mission controllers never lose contact," it said.

The stations communicate with the spacecraft, monitor its movement and relay data back to mission control.

Southern hemisphere stations like Hartebeesthoek are indispensable, particularly for missions that travel beyond Earth’s immediate orbit.

SANSA's role was deceptively simple in description but exacting in execution, Hodges told South African digital news platform News 24 in April.

"You track, you listen, and you make sure the spacecraft is where it’s supposed to be," he said.

He said this arrangement reflected the global nature of modern spaceflight and that no single country could maintain uninterrupted contact with a spacecraft throughout its journey.

SANSA’s work is time-bound and has to be precise, he added, explaining that its antennas lock onto the spacecraft during designated windows, gathering data before handing over to the next station in the network.

Those windows become critical during key phases of a mission, such as reentry, when astronaut safety is on the line.

"There are certain maneuvers where you need absolute certainty about where that spacecraft is. That’s when multiple stations are often used at the same time, with backups in place," Hodges said.

South Africa's contribution

South Africa’s involvement in the Artemis II mission was built on decades of cooperation with NASA, with SANSA’s involvement reflecting a more active African role in international space efforts.

Ground stations in South Africa have supported satellite tracking and deep-space missions since the mid-20th century. Over time, these systems were upgraded to handle higher data volumes and more precise navigation requirements.

Providing tracking and communications support for a crewed mission demonstrated how African institutions are taking on more technical responsibilities within international programs.

This shift has come as more countries on the continent invest in space capabilities and seek international governmental and commercial partnerships.

The Artemis program is built on contributions from multiple countries, with each providing specific systems or services.

Ground stations are one part of that structure.

The Artemis program is intended to return astronauts to the moon and support longer-term manned-space exploration. Artemis II served as an early step in that process, testing systems needed for later missions.

While South Africa has contributed to space missions for decades, its role has often been less visible than that of launching nations. Its involvement in Artemis II highlighted how that is changing.

As more missions are planned and launched, the need for ground-based tracking and communications is expected to continue. South Africa’s existing infrastructure and experience position it to remain involved in these efforts.

Speaking to Biz News, Hodges highlighted a strategy to grow the country's space sector and bring young people into it through training and education, with the goal of creating a pipeline of highly skilled professionals.

These locally-trained engineers, technicians, operators and artisans will be ready to support other international space missions.

South Africa also is investing in new infrastructure to expand its influence in the international space community, with plans to develop a ground station in Matjiesfontein.

Construction is under way, and the site is expected to be operational by the third quarter of this year, according to Space in Africa.

The new antenna facility will be crucial in spacecraft tracking and communications, leveraging the site's favorable geographic location and atmospheric conditions.

This will extend South Africa's tracking range and increase its capacity to support future missions to the moon and beyond.