While tracking more and more objects orbiting Earth is crucial to ensure a safe operating environment, so is the ability to identify them correctly.
Space-Track, provided by the U.S. Space Force’s 18th Space Squadron (18 SDS), offers one of the most comprehensive databases of orbital observations.
However, more than 300 objects 18 SDS tracks in low Earth orbit were listed as unidentified at press time.
Understanding where these objects came from and characterizing their attributes is critical for keeping space sustainable, according to Australian space situational awareness (SSA) startup High Earth Orbit Robotics.
Correctly identifying them as functioning satellites is important for international law and spectrum regulation.
If they are debris, their identification helps determine whether they pose a threat, how similar debris could be avoided, and supports their management and potential removal.
A case in point is an unexpected object that reached orbit last year with nine Chinese satellites, dubbed Object K, which HEO Robotics says is likely a piece of rocket debris.
The startup is building its own database of in-orbit objects using images acquired by taking control of satellites from Earth observation partners.
When these satellites are not being used — such as over an ocean if the operator focuses on land imagery — they are momentarily tilted so an onboard camera can snap objects they fly past.
Using this method, HEO Robotics says Object K is likely half of a Chinese Long March 6 payload fairing that deployed the satellites in April 2021.
The nine satellites are research spacecraft for applications that include remote sensing services, according to Chinese state media that did not mention the tenth object.
Object K’s unexpected location could be due to a partial failure of a mission-standard explosive bolt component, HEO Robotics said.
Although the startup says it has conducted multiple visual inspections of these 10 objects, they are still officially unidentified under Space-Track.
Object K is in “a super busy region of space” with an orbit that intersects many other objects, HEO Robotics CEO William Crowe said, and poses a risk to the International Space Station and Chinese Space Station as its orbit evolves.
“I think the bigger risk is to people and property on Earth,” Crowe added, “we now know this is an uncontrolled object that will reenter from an orbit it was never meant to be in.”
Plenty of Long March payload fairings have been recovered almost intact in the Chinese countryside soon after launch.
Sometimes the U.S. military knows what the object is but does not want to disclose it publicly because it relates to national security intelligence capabilities, said Brian Weeden, director of program planning at the Secure World Foundation.
But in “many cases, they don’t know what it is,” said Weeden, who used to work on SSA programs at the U.S. Air Force.
The U.S. military has listed improving space domain awareness as a high priority for more than a decade, and a variety of efforts are underway to improve its ability to track, identify, and characterize in-orbit objects.
HEO Robotics, ground-based radar operators, and other private companies are helping to bring more data to the equation; however, there remains a disconnect between them and the DoD.
Part of the reason is the U.S. military “still has in most cases very antiquated, outdated computer and IT systems, and systems in general that were not built to pull in data from outside sources,” Weeden said.
There’s also “a bureaucracy that is still largely skeptical of commercial,” he added, particularly where there are overlaps with government or government-funded programs.
Ensuring Space-Track’s accuracy requires cooperation between satellite operators, their owners, and the DoD, said U.S. Space Force Lt. Col. Matthew Linkter, commander of 18 SDS.
18 SDS “makes every effort to establish relationships with new satellite operators, launch agencies, and service providers” to identify all artificial objects on orbit and keep Space-Track updated, he said.
“However, not all satellite operators willingly share the information needed to effectively identify space objects, which leads to unnamed objects in the catalog.”
While 18 SDS “accepts and considers feedback from a variety of space stakeholders who have reliably provided or published spacecraft identifications,” he said receiving data directly from the operator/owner is most valuable.
Especially “since it allows us to establish data sharing relationships that ensure long-term spaceflight safety.”
This article originally appeared in the October 2022 issue of SpaceNews magazine.
