In a tense moment for space safety, two satellites—NASA’s TIMED spacecraft and the defunct Russian Cosmos 2221—came alarmingly close to smashing into each other above Earth, prompting concerns about the risks of space debris.
The near miss happened Wednesday arvo as the two satellites brushed past each other some 378 miles (608 kilometers) above Earth, according to LeoLabs, a California-based company specializing in tracking and analyzing objects in Low Earth Orbit.
The satellites in question were NASA’s Thermosphere Ionosphere Mesosphere Energetics and Dynamics Mission (TIMED) spacecraft, launched in 2001 to study the Sun and Earth’s upper atmosphere, and the Russian Cosmos 2221, a defunct defense satellite launched in 1992. LeoLabs reported that the two satellites came within a mere 66 feet (20 meters) of each other. Considering the speed at which these objects travel–over 17,500 miles per hour (28,165 kilometers per hour)–this was “too close for comfort,” as the company said on X. Both of these spacecraft lack maneuverability, leaving ground observers with no choice but to watch helplessly, without the ability to intervene.
“Indeed, the two satellites likely passed within 20 meters of each other,” LeoLabs’ senior technical fellow Darren McKnight explained to Gizmodo in an email. “We monitor over 20,000 objects in Low Earth Orbit (LEO) using our 10 phased array radars worldwide. We can identify and update the orbital trajectories of all of these objects several times a day.”
NASA, in a statement, acknowledged that, had the satellites collided, it would have led to “significant debris generation.” Such an event would have increased the risk of further collisions in a wide area of LEO, particularly affecting the lower orbits frequently used by satellite constellations and crewed space missions.
LeoLabs further analyzed the potential impact of a collision, suggesting it could have generated approximately 2,000 to 7,000 trackable fragments. This estimate considers the total mass, construction, relative velocity, and the angle of impact of the spacecraft. As of February 15, there are around 12,000 fragments in LEO, and this incident could have potentially increased this number by 50%, the company claims.
Such near-misses are rare, according to LeoLabs, with only six events in the past two years featuring a miss distance of less than 66 feet between “two intact, non-maneuverable objects.” Clearly, this latest incident highlights the growing concerns over space debris and the need for improved monitoring and mitigation strategies to ensure the safety of current and future space missions.
“This event is indicative of an increasing number of near misses in LEO,” McKnight said. “Some altitude regions are worse than others, but generally half of the population in LEO is comprised of fragments and massive derelict objects,” including abandoned rocket bodies and non-operational payloads. Large derelict objects represent just 12% of the total number in space, he said, yet they account for 45% of the total mass. This is significant, as collisions between these large objects can create thousands of fragments, escalating the risk of further impacts. “Lastly, constellations of smallsats are being deployed on a regular basis and their resiliency requires space traffic coordination processes and technologies to ensure their long-term safe operations,” McKnight added.
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To date, only once has a satellite smashed into another. This occurred in 2009 when Iridium 33, a U.S. communications satellite, and Kosmos-2251, a defunct Russian military satellite, collided in orbit some 490 miles (789 kilometers) above Siberia. It’s the most “severe accidental fragmentation on record,” with the event producing more than 1,800 pieces of debris larger than 3.9 inches (10 centimeters), according to NASA.
Thankfully, incidents like this should decrease over time owing to newly implemented rules from the Federal Communications Commission, which require satellite providers to retire their satellites within five years of completing their missions, reducing the risk of space debris and potential collisions.