According to a report by Hong Kong's South China Morning Post on September 28, Chinese researchers have announced a closely watched spaceflight breakthrough: a satellite in China's BeiDou navigation system is said to have undergone an on-orbit refueling operation in space. If accurate, the claim would put China at the forefront of satellite servicing and life-extension technology worldwide, and could have far-reaching implications for the global space race.

According to a paper produced by the state-backed Deep Space Exploration Laboratory — currently still under peer review at the Journal of Deep Space Exploration — and details disclosed in a separate study published in April by researchers from the Chinese Academy of Sciences in the International Journal of Aerospace Engineering, the servicing spacecraft that carried out the refueling was Shijian-25. The satellite was launched on January 7, 2025, from the Xichang Satellite Launch Center aboard a Long March-3B rocket, and was developed by the Shanghai Academy of Spaceflight Technology. At the time, the developer publicly described Shijian-25's mission as testing technologies for satellite on-orbit refueling and life-extension services, as well as satellite repair and space-debris removal.

The paper states that in February 2025, Shijian-25 conducted a rendezvous and docking with the BeiDou-2 G7 navigation satellite at geostationary orbit altitude, transferring 142 kilograms of room-temperature propellant to it — a transfer said to extend BeiDou-2 G7's operational lifespan by roughly eight years. Researchers noted that carrying out refueling operations at medium Earth orbit and geostationary orbit altitudes, tens of thousands of kilometers above Earth, is extremely challenging: the servicing spacecraft must precisely locate, approach and match orbits with a target satellite traveling at several kilometers per second, then dock at extremely close range, where even a slight deviation could result in a collision.

The claim was first put forward in the Deep Space Exploration Laboratory paper, which remains under peer review and has not yet been formally published; the Chinese Academy of Sciences study published in April further confirmed the identities of the servicing spacecraft, Shijian-25, and the target satellite, BeiDou-2 G7. Both studies describe the event as China's first successful on-orbit refueling of a high-orbit navigation satellite.

Notably, China's BeiDou navigation system underwent a significant in-orbit capability upgrade this year, providing broader context for the refueling claim. According to a Xinhua report on July 31, BeiDou completed a fleet-wide in-orbit software upgrade, carried out by transmitting secure commands from the Xi'an Satellite Control Center to all 50 operational satellites spread across three different orbital regimes, without requiring any new satellite launches. Following the upgrade, the BeiDou system's global positioning accuracy improved to better than 10 metres, velocity-measurement accuracy to better than 0.2 metres per second, and timing accuracy to within 20 nanoseconds; its Precision Point Positioning (PPP) service achieved horizontal accuracy better than 0.3 metres for the first time and vertical accuracy better than 0.6 metres, the highest level since the system was completed. Analysts say that against this backdrop, if on-orbit refueling technology matures and becomes routine, it would extend the service life of existing high-orbit satellites such as BeiDou-2 G7, complementing the software upgrade and further reinforcing BeiDou's global competitiveness.

However, the breakthrough claim has also faced considerable skepticism. According to the South China Morning Post, orbital tracking data compiled by the U.S. Space Force appears to contradict the rendezvous described by the Chinese researchers. Independent astrophysicist Jonathan McDowell, after analyzing the relevant tracking data, noted that in early 2025, BeiDou-2 G7 and Shijian-25 maintained a longitudinal separation of roughly 10 degrees in geostationary orbit throughout the period in question; based on the two satellites' drift rates at the time, he concluded that an undetected docking would have been physically implausible unless the tracking networks had misidentified the target objects. He also pointed out that neither the still-unpublished paper nor the Chinese Academy of Sciences study cites any externally verifiable data source to support the claim that refueling actually took place.

Notably, this is not the first time China's on-orbit operations in this area have drawn attention. According to earlier reporting, in the summer of 2025 China maneuvered two satellites, Shijian-21 and Shijian-25, into extremely close proximity in geostationary orbit to conduct what was believed to be a satellite-refueling-related experiment. Separately, Shijian-21 had previously, in 2022, grappled a defunct BeiDou-2 G2 satellite and towed it into a disposal "graveyard orbit" well away from normal operational orbits — a closely watched earlier public demonstration of China's on-orbit servicing capability.

From a broader perspective, the BeiDou system has for years been viewed as a strategic infrastructure project through which China seeks to rival the U.S. GPS system, with Beijing continuing to promote BeiDou's adoption in countries along the Belt and Road and push forward international standardization, aiming to expand BeiDou's share of the global satellite navigation market. The South China Morning Post has previously reported along similar lines under headlines describing BeiDou as "China's GPS rival" expanding global adoption through upgrades. Against this backdrop, regardless of whether the specific details of this on-orbit refueling claim are ultimately independently verified, the signal sent by the announced breakthrough itself — that China is systematically investing resources to enhance its ability to independently maintain and sustain the long-term reliability of its satellite constellation — is likely to be seen as part of BeiDou's competition in the global navigation market, and of the broader U.S.-China space rivalry.

In terms of strategic significance, analysts say that if on-orbit refueling technology matures and is deployed at scale, it would substantially enhance the maneuverability of satellites — particularly dual-use military and civilian satellites — allowing them to adjust their orbital positions more frequently and unpredictably, evade adversaries' tracking and surveillance networks, reposition in response to co-orbital threats, and conduct close-range inspection of other spacecraft on demand. For China, whose satellite launch and replenishment capacity lags behind that of the United States, on-orbit refueling is seen as a strategically valuable "force multiplier" technology that could extend the operational life of existing satellite constellations and reduce the cost pressure of frequently launching replacement satellites.

At the same time, the United States has also been building capability in this area. Northrop Grumman's Mission Extension Vehicle (MEV) program has, since 2020, provided on-orbit servicing to commercial satellites in geostationary orbit, with its two MEV spacecraft having together provided more than ten years of combined life-extension service to several commercial communications satellites. The company also launched its Mission Robotic Vehicle (MRV) this year, equipped with robotic arms capable of performing satellite repair and refueling tasks, and carrying the U.S. Space Force's first approved refueling-interface standard, the Passive Refueling Module. Reports indicate that the U.S. Office of the Director of National Intelligence assesses China will become the United States' most significant rival in space by 2040, and that the Pentagon has reportedly been closely monitoring China's on-orbit maneuvering and refueling activities.

Overall, although the claimed BeiDou satellite on-orbit refueling breakthrough has yet to be independently corroborated and international opinion on its authenticity remains clearly divided, the episode itself reflects how on-orbit servicing and satellite life-extension technology are rapidly becoming a new focal point of the U.S.-China space race. The transparency of this capability, the degree to which it can be independently verified by third parties, and the controversies its possible military applications could raise are all likely to continue drawing international scrutiny in the period ahead.