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China’s Long March 6A rocket is making a mess in low-Earth orbit

Another one —

After nearly every flight, the upper stage of this rocket breaks apart in orbit.

Debris from the upper stage of China's Long March 6A rocket captured from the ground by Slingshot Aerospace.

Enlarge / Debris from the upper stage of China’s Long March 6A rocket captured from the ground by Slingshot Aerospace.

The upper stage from a Chinese rocket that launched a batch of Internet satellites Tuesday has broken apart in space, creating a debris field of at least 700 objects in one of the most heavily-trafficked zones in low-Earth orbit.

US Space Command, which tracks objects in orbit with a network of radars and optical sensors, confirmed the rocket breakup Thursday. Space Command initially said the event created more than 300 pieces of trackable debris. The military’s ground-based radars are capable of tracking objects larger than 10 centimeters (4 inches).

Later Thursday, LeoLabs, a commercial space situational awareness company, said its radars detected at least 700 objects attributed to the Chinese rocket. The number of debris fragments could rise to more than 900, LeoLabs said.

The culprit is the second stage of China’s Long March 6A rocket, which lifted off Tuesday with the first batch of 18 satellites for a planned Chinese megaconstellation that could eventually number thousands of spacecraft. The Long March 6A’s second stage apparently disintegrated after placing its payload of 18 satellites into a polar orbit.

Space Command said in a statement it has “observed no immediate threats” and “continues to conduct routine conjunction assessments to support the safety and sustainability of the space domain.” According to LeoLabs, radar data indicated the rocket broke apart at an altitude of 503 miles (810 kilometers) at approximately 4: 10 pm EDT (20: 10 UTC) on Tuesday, around 13-and-a-half hours after it lifted off from northern China.

At this altitude, it will take decades or centuries for the wispy effect of aerodynamic drag to pull the debris back into the atmosphere. As the objects drift lower, their orbits will cross paths with SpaceX’s Starlink Internet satellites, the International Space Station and other crew spacecraft, and thousands more pieces of orbital debris, putting commercial and government satellites at risk of collision.

A new debris field of nearly 1,000 objects would be a significant addition to the approximately 46,000 objects Space Command tracks in Earth orbit. According to statistics compiled by Jonathan McDowell, an astrophysicist who monitors global launch and spaceflight activity, this would rank in the top five of all debris-generation events since the dawn of the Space Age.

This rocket has a track record

The medium-class Long March 6A rocket has launched seven times since debuting in March 2022, and military and commercial satellite tracking organizations have reported several breakups of the rocket’s upper stage. In November 2022, a Long March 6A upper stage disintegrated in orbit, creating a debris field of more than 500 trackable objects, according to NASA’s Orbital Debris Program Office.

Commercial satellite tracking companies observed smaller debris fields following several other Long March 6A flights this year.

In its space environment statistics report, the European Space Agency says there have been more than 640 “breakups, explosions, collisions, or anomalous events resulting in fragmentation” in orbit. So these things happen frequently. But it’s not clear what makes the Long March 6A, which has a relatively short flight history, particularly vulnerable to creating debris.

A Long March 6A rocket launches the first 18 Internet satellites for China's Qianfan, or Thousand Sails, broadband network.

Enlarge / A Long March 6A rocket launches the first 18 Internet satellites for China’s Qianfan, or Thousand Sails, broadband network.

Most rockets operating today either reignite their engines to reenter the atmosphere after deploying their payloads, or if that’s not feasible, they “passivate” themselves to empty their propellant tanks and drain their batteries to reduce the risk of an explosion.

In a report last year, NASA’s Orbital Debris Program Office said the Long March 6A upper stage has a mass of about 5,800 kilograms (12,800 pounds) without kerosene and liquid oxygen propellants. It is powered by a single YF-115 engine.

The launch Tuesday began the deployment of China’s “Thousand Sails” Internet network, which will initially consist of 1,296 satellites, with the possibility to expand to more than 14,000 spacecraft. This will require numerous launches, some of which will presumably use the Long March 6A.

“If even a fraction of the launches needed to field this Chinese megaconstellation generate as much debris as this first launch, the result would be a notable addition to the space debris population in LEO (low-Earth orbit),” said Audrey Schaffer, vice president of strategy and policy at Slingshot Aerospace, a commercial satellite tracking and analytics firm.

China has been responsible for several space debris incidents beyond the latest problems with the Long March 6A rocket. In 2007, China destroyed one of its own spacecraft in an anti-satellite missile test. This was the worst-ever instance of creating space debris, resulting in more than 3,000 trackable objects, and an estimate 150,000 or more smaller fragments.

On four occasions from 2020 through 2022, the massive core stage of China’s heavy-lift Long March 5B rocket has reentered the atmosphere in an uncontrolled manner, raising concerns that falling debris could put people and property at risk on Earth.

China plans more flights with its Long March 5B and Long March 6A rockets. China continued flying the Long March 5B rocket despite the risk it posed to people on the ground. Debris fields in orbit, however, don’t directly threaten any people on Earth, but they do raise the risk to satellites of all nations, including China’s own spacecraft.

“Events like this highlight the importance of adherence to existing space debris mitigation guidelines to reduce the creation of new space debris and underscore the need for robust space domain awareness capabilities to rapidly detect, track, and catalog newly-launched space objects so they can be screened for potential conjunctions,” Schaffer said in a statement.

This story was updated with the detection of additional debris fragments by LeoLabs.

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China begins launching a megaconstellation, and it sounds a lot like Starlink

Sailing in LEO —

Like Starlink, China’s Qianfan satellites have an easy-to-pack flat-panel design.

A Long March 6A rocket launches the first 18 Internet satellites for China's Qianfan, or Thousand Sails, broadband network.

Enlarge / A Long March 6A rocket launches the first 18 Internet satellites for China’s Qianfan, or Thousand Sails, broadband network.

Chinese officials have long signaled their interest in deploying a satellite network, or maybe several, to beam broadband Internet signals across China and other nations within its sphere of influence.

Two serious efforts are underway in China to develop a rival to SpaceX’s Starlink network, which the Chinese government has banned in its territory. The first batch of 18 satellites for one of those Chinese networks launched into low-Earth orbit Tuesday.

A Long March 6A rocket delivered the 18 spacecraft into a polar orbit following liftoff at 2: 42 am EDT (06: 42 UTC) from the Taiyuan launch base in northern China’s Shanxi province. The Long March 6A is one of China’s newest rockets—and the country’s first to employ strap-on solid rocket boosters—with the ability to deploy a payload of up to 4.5 metric tons (9,900 pounds) into a 700-kilometer (435-mile) Sun-synchronous orbit.

The rocket placed its payload of 18 Qianfan satellites into the proper orbit, and the launch mission was a complete success, according to the China Aerospace Science and Technology Corporation, the largest state-owned contractor for the Chinese space program.

Qianfan translates to “Thousand Sails,” and the 18 satellites launched Tuesday are the first of potentially thousands of spacecraft planned by Shanghai Spacecom Satellite Technology (SSST), a company backed by Shanghai’s municipal government. The network developed by SSST is also called the “Spacesail Constellation.”

Shanghai officials only began releasing details of this constellation last year. A filing with the International Telecommunication Union suggests the developers of Shanghai-based megaconstellation initially plan to deploy 1,296 satellites at an altitude of about 1,160 kilometers (721 miles).

Xinhua, China’s state-run news agency, said the constellation “will provide global users with low-latency, high-speed and ultra-reliable satellite broadband Internet services.”

Opening the floodgates?

SSST’s network was previously known as G60 Starlink, referencing a major cross-country highway in China and the project’s intent to imitate SpaceX’s broadband service.

Thousand Sails may eventually consist of more than 14,000 satellites, but like other Internet megaconstellations, the size of the fleet will likely grow at a rate commensurate with demand. It will take many years for SSST to deploy a 14,000-satellite constellation, if it ever does. SpaceX has rolled out several generations of Starlink satellites to offer new services and more capacity to meet customer uptake.

Chinese officials have released few details about the Qianfan satellites. But the project’s backers have said the spacecraft has a “standardized and modular” flat-panel design. “It meets the needs of stacking multiple satellites with one rocket,” said Shanghai Gesi Aerospace Technology, a joint venture set up by SSST and the Chinese Academy of Sciences to oversee manufacturing of Qianfan satellites.

This sounds a lot like the design of SpaceX’s Starlink satellites, which are flat-packed for launch on Falcon 9 rockets. SpaceX pioneered this way of launching and deploying large numbers of satellites. The approach used for Starlink, and apparently for Qianfan, streamlines the integration of multiple satellites with their launcher on the ground. It also simplifies their separation from the rocket once in orbit.

The new Qianfan satellite factory in Shanghai can produce up to 300 spacecraft per year, project officials said in December. Officials previously said the first 108 satellites for the Thousand Sails constellation would launch this year.

SSST announced in February it had raised more than $900 million from Chinese state-backed investment funds, Shanghai’s municipal government, and sources of venture capital. SSST’s origin is linked to a Chinese joint venture with a Germany-based company called KLEO Connect, which intended to develop a smaller constellation of low-Earth orbit satellites for data relay services.

China launched four technology demonstration satellites, purportedly related to the KLEO Connect venture, to test telecom hardware and electric propulsion systems in orbit. The joint venture fell apart with a flurry of lawsuits, and the German government last year blocked a complete takeover of KLEO Connect by its Chinese investors.

Now, SSST is going it alone with the Thousand Sails network. It has rapidly scaled up satellite manufacturing capacity in Shanghai. But outside of Starlink, companies with ideas for megaconstellations have run into serious headwinds.

OneWeb filed for bankruptcy in 2020 before eventually launching its entire first-generation network of 633 Internet satellites. Amazon has pushed back the full-scale deployment of its Project Kuiper megaconstellation, and the launch of the first operational Kuiper Internet satellites may be delayed again to 2025. The future of the European Union’s IRIS² satellite Internet network is in doubt after disagreements among European governments on funding the project.

The Thousand Sails constellation is less well-known than another planned Chinese satellite Internet network known as Guowang, or “national network,” which is supported by China’s central government. Guowang is owned by a state-backed company called SatNet, and its architecture will consist of 13,000 satellites. However, China has not yet launched any spacecraft for the Guowang project.

It’s unclear if the Thousand Sails network and the Guowang constellation will be direct competitors. They could be geared to different segments of the broadband market. In either case, China’s restrictive Internet policies with terrestrial networks will likely spill over into the satellite segment.

Chinese officials recognize the military utility of satellite Internet services like Starlink, which has supported Ukrainian military forces fighting Russian troops since 2022. A homegrown Starlink-like service would, no doubt, prove useful for China’s military.

Alongside potential domestic civilian users, China could use its satellite Internet networks as a diplomatic tool to build on existing partnerships between the Chinese government and developing countries. This could “lead to a leapfrogging moment, where African countries opt for the Chinese Internet constellation over Western providers due to the fact that much of their infrastructure is already Chinese-built,” the Royal United Services Institute, a UK think tank, wrote in a report last year.

While there are open questions about how China will use its satellite megaconstellations, their deployment will require a significant increase in the country’s launch capacity, driving the development of new commercial rockets, including reusable boosters, to lower costs and increase their flight rate.

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