China’s Three-Satellite Constellation Is The First Of Its Kind For Use In The Earth-Moon Region

In a new achievement for the region, China has officially established the world’s first three-satellite constellation for use in the Earth-Moon region. This constellation is in distant retrograde orbit between the Earth and the Moon, and to maintain connection among these satellites, China relies on stable inter-satellite measurement and communication links.

Here’s Why China’s Three-Satellite Constellation Is Remarkable

In a recent interview, researchers at the Chinese Academy of Sciences (CAS) shared some information on the constellation.

This constellation orbits the Earth-moon region, which the agency refers to as the “expanded domain extending outward from Earth’s orbit.” This domain reaches 2 million kilometres and features a three-dimensional volume that expands over a thousand times.

The foundation of this is years of research work focusing on the Earth-Moon region of space astrodynamics and space exploration. The constellation trades “longer flight time for increased payload capacity and greater contingency margin.”

Researchers at CAS were able to build a constellation which can complete the Earth-Moon transfer while using only one-fifth of the traditionally required fuel. The Chinese three-satellite constellation became the world’s first constellation to complete low-energy insertion into the distant retrograde orbit (DRO).

The constellation is also the first in the world to successfully verify a 1.17-million-kilometre K-band inter-satellite microwave measurement and communication link.

Also, the entire build of this constellation doesn’t require a traditional ground-based tracking system like most other constellations. Instead, it relies on a system where the satellites track each other, hence ensuring orbit determination accuracy faster than most ground-based tracking systems.

Wang Wenbin, a researcher at the CAS Centre for Space Utilization (CSU) says that this tracking system “opens a new technical pathway for China’s future cislunar and deep space exploration.” He adds that the tracking system “provides an efficient solution for orbit determination, navigation, and timing across various cislunar orbits, supporting the future expansion of large-scale commercial activity in cislunar space.”

When Did The China Three-Satellite Constellation Launch?

The CAS kicked off original research and key technology development for this constellation in 2017.

The project’s pilot program was initiated in February 2022 with the aim of developing the three-satellite constellation. Making up the constellation are satellites DRO-A, DRO-B, and DRO-L, with the last two staying in Earth-moon space manoeuvre orbits and DRO-A orbiting the Moon.

DRO-L was the first satellite of the three to launch into space in February 2024. The other two satellites were launched in March 2024 and got into mission orbit on 15 July 2024.

In August 2024, all three satellites formed the constellation for the first time since they all got into orbit. With lots of lunar missions in place for the coming years, we might get to see how this constellation helps China explore the Moon.