Space, just beyond Earth’s atmosphere, is starting to take on the appearance of a cluttered teenager’s bedroom: no matter how hard we clean it up, it just keeps getting messier. That’s one of the stark findings of the 2024 Space Environment Report, published July 23 by the European Space Agency. The report, which has been an annual publication since 2017, functions as a census for activities in space, and it highlights a growing problem: space debris.
It states that surveillance networks are now tracking over 35,000 objects orbiting Earth, with some 26,000 of those being pieces of junk bigger than 4 inches in diameter. Better attempts recently are being made to mitigate this vast accumulation of space junk, but it just keeps on piling up and creating, according to the report, “an unsustainable environment in the long term.”
SpaceX has revealed its mega-constellations of 6,200 satellites in the Starlink network executed almost 50,000 maneuvers of collision avoidance within a year to avoid junk in low-Earth orbit. It also shared that, on Earth, it had a close call back in May when pieces of one of its Crew Dragon spacecraft crashed in the mountains of North Carolina, impacting private homes.
The ESA report reveals that satellite launches have dramatically increased, much of which is commercial, for example, SpaceX’s Starlink. Now, more than 6,000 active satellites are in low-Earth orbit at altitudes between 310 and 370 miles. This region has become crowded increasingly, and nearly all satellites launched in the year 2023 are destined for these altitudes. Such a collision or explosion in this busy space freeway could trigger a catastrophic chain reaction, endangering the very engines of critical infrastructure, from space telescopes to low-orbit space stations.
There are, however, some bright spots to report. One such growing trend in reducing space junk, according to the report, involves deorbiting payloads and spent rocket bodies. In 2023, a significant rise in payload re-entries was seen, over 600 objects tumbled back to Earth in an uncontrolled manner. This increase is partially attributed to heightened solar activity that causes the upper atmosphere to balloon, bringing low-Earth orbit objects down faster.
All these efforts notwithstanding, compliance continues to be an issue. Indeed, too many of the larger payloads at the end of their missions aren’t successfully removing themselves from orbit, therefore contributing to the growing debris problem. ESA expects the number of catastrophic collisions to rise sharply over a few centuries, with smaller rises expected in the coming decades.
According to Mars Buttfield-Addison, a PhD researcher at the University of Tasmania and Australia’s CSIRO, “Overall, the report is full of bad news that is good news.” He says lots of very clever and highly motivated people are working on mitigation strategies; however, physics, commercial interests, and international law too often conspire against them.
The ESA and some of its member states have just signed the nonbinding Zero Debris Charter, committing to take steps to deal with the orbital debris problem. There is a growing need for a global framework against the uneven results from past efforts by individual space-active nations and a dangerous environment of junk orbiting Earth.
In summary, though many efforts are underway to mitigate the space debris crisis, its implementation is still inadequate to establish a sustainable environment in the long term. This report accentuates the fact that it is very important to double down on the strategies aimed at reining in this escalating threat.