Space Command chief says dialogue with China is too often a one-way street

The head of US Space Command said Wednesday he would like to see more transparency from the Chinese government on space debris, especially as one of China's newer rockets has shown a propensity for breaking apart and littering low-Earth orbit with hundreds of pieces of space junk.

Gen. Stephen Whiting, commander of US Space Command, said he's observed some improvement in the dialogue between US and Chinese military officials this year. But the disintegration of the upper stage from a Long March 6A rocket earlier this month showed China could do more to prevent the creation of space debris, and communicate openly about it when it happens.

The Chinese government acknowledged the breakup of the Long March 6A rocket's upper stage in a statement by its Ministry of Foreign Affairs on August 14, more than a week after the rocket's launch August 6 with the first batch of 18 Internet satellites for a megaconstellation of thousands of spacecraft analogous to SpaceX's Starlink network.

Space Command reported it detected more than 300 objects associated with the breakup of the upper stage in orbit, and LeoLabs, a commercial space situational awareness company, said its radars detected at least 700 objects attributed to the Chinese rocket.

"I hope the next time there's a rocket like that, that leaves a lot of debris, that it's not our sensors that are the first to detect that, but we're getting communications to help us understand that, just like we communicate with others," Whiting said at an event hosted by the Mitchell Institute marking the fifth anniversary of the reestablishment of Space Command.

Whiting said he didn't have any technical details about why the Long March 6A rocket's upper stage broke apart, but it happened after the rocket deployed all of its payloads. "They had already released the satellites at that point, and it seems like the mission was overall successful, but all this debris gets left in orbit," he said. "We certainly don't want to see that kind of debris."

Due regard

The Space Force's 18th Space Defense Squadron, located at Vandenberg Space Force Base in California, is responsible for tracking objects in Earth orbit, maintaining a catalog of all satellites and space junk, and monitoring for potential collisions between spacecraft or debris. Space Command regularly issues warnings of conjunctions, or close approaches, between objects to commercial companies and foreign governments.

"For decades now, the United States has so cared about the space domain that we have made available the vast majority of tracking data that we have, for free, for the world," Whiting said. "Every day, we screen every active satellite against all that debris, and we provide notifications out to everyone, including the Chinese and Russians.

"People sometimes ask, 'Well, why do you do that?' Well, it's because we don't want satellites to run into pieces of debris and create more debris. So we think it's really important, and we have a set of responsible behaviors that we follow each and every day. We provide these notifications to the Chinese," Whiting said.

The Commerce Department plans to take over some of the military's role in space traffic management, but Space Command will maintain its own catalog and will remain responsible for working with foreign militaries on space debris matters, according to Whiting.

Last November, President Joe Biden and Chinese President Xi Jinping agreed to resume military-to-military communications between each nation's armed forces, which were suspended in 2022. US and Chinese military leaders have met face-to-face several times this year, and Jake Sullivan, Biden's national security advisor, met with Xi and Chinese military leaders this week in Beijing. The meetings have focused on terrestrial concerns and operational matters, such as reducing the risk of miscalculations, or an accidental escalation or conflict between Chinese airplanes and ships and those from the United States and its allies.

Whiting said China has provided the US military with some information on the topic of space debris, but China should do more.

"Over the last year, we've seen a couple of times that they've given us a few notifications back, and I think that's positive," he said. "But we've also just seen the launch of their version of a [Internet] constellation that left 300-plus pieces of debris in orbit—a Long March 6A. Less than two years ago, they had another (Long March 6A) that I think put up another 500 pieces of long-lived debris."

The Long March 6A rocket that spread debris in orbit this month broke apart at an altitude of approximately 500 miles (800 kilometers). 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.

The medium-class Long March 6A rocket has launched seven times since debuting in March 2022. Nearly every mission of the Long March 6A has left behind at least a small cloud of debris in orbit. The two most significant debris-generating events were following a launch in November 2022 and the breakup of the upper stage this month.

"In our tenets of responsible behavior, three things would apply here," Whiting said. "No. 1, that we all should operate with due regard and in a professional manner. No. 2, that we should limit the amount of long-lived debris that we have. And No. 3, that we communicate and promote safety with other actors in the domain."

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

US launch companies typically either reserve enough propellant on their upper stages to remove them from orbit after they deploy their payloads, or vent their tanks and drain their batteries to reduce any explosive hazards if the rockets will remain adrift in space. Russian rockets also do this.

But China has a track record of leaving behind a lot of space junk. LeoLabs says there are nearly 1,000 abandoned rocket bodies in low-Earth orbit, with an average mass of 1.5 metric tons.

"That number continues to grow, posing a significant risk to the space environment," LeoLabs said in a statement. "While Russia and the US have improved their 'rocket body abandonment behavior' over the last 20 years, the relative contribution by other countries has grown by a factor of five and China by 50x.

"The rate that China is leaving abandoned rocket bodies in orbit reverses the improved behavior of US and Russia and results in a continual accumulation of objects that will be especially prolific in creating fragments if involved in a collision," LeoLabs engineers wrote in a paper last year.

LeoLabs researchers found the total mass of all rocket hardware in low-Earth orbit (LEO) is currently nearly 1,500 metric tons. "Sadly, the rate of rocket body mass abandonment in LEO has actually increased in the last 20 years relative to the first (approximately) 45 years of the space age."