As traditional satellite providers launch new satellites into Geostationary Earth Orbit (GEO) and Medium Earth Orbit (MEO) – and as new entrants into the industry begin to populate Low Earth Orbit (LEO) with large constellations with thousands of satellites – some may look to the sky and see a new, burgeoning space age. Others may see the proliferation of satellites across many different orbits as the driver to digital transformation for governments and organizations across the globe – even in places with little to no terrestrial network connectivity.
Then, there are those that see a massive influx of new satellites and the introduction of proposed “kilofleets” at LEO and see a problem. They may realize that – with many new satellites being launched – the potential for collisions that create harmful space debris increases exponentially.
These individuals may be thought of as pessimists, but they’re most likely just realists – seeing the obvious truth that more means more, and increased objects and spacecraft traveling through space is a recipe for those objects to come into contact with each other.
With “kilofleets” like the SpaceX Starlink fleet that is expected to be comprised of satellites that number in the tens of thousands – and other large LEO fleets on the way – it’s time for the industry and government to start giving real thought to the issue of space debris and satellite collisions. It’s also time to start thinking about how large numbers of new objects in space influence other space activities – such as the availability of launch windows.
Included in this discussion should not only be conversations about mitigating the generation of future space debris – but also cleaning space of the debris that already exists to make it safer for all satellite and launch operators. That discussion also has to include who is responsible for collisions, and just what should commercial operators be required to do to protect their space assets.
But before we jump into those difficult topics, let’s explore the current state of space debris at LEO.
Disposable satellites in a congested space
To some members of the space industry, early cubesats were thought of as space trash. However – much like a message in a bottle can be seen as communication by some, and as litter by others – some in the satellite industry and academia saw early cubesats as precursors to an important and innovative new space technology.
As technology has miniaturized, small satellites – even CubeSats – are now being built, launched, and operated that provide value-added services sufficient to close a business case. However, many of the early cubesats that remain – and some that are still being built – are considered disposable by those that built and launched them.
The increased numbers of satellites in LEO will eventually become a problem as soon as one or two major collisions significantly contaminate the orbit. And, as long as LEO satellites are viewed as disposable, this risk will continue to build.
“Space has already become a warfighting domain, and today’s coalition governments and military forces don’t need the added threat to their space assets and spacecraft that is posed by space debris.”
Luckily, this is a risk that is being somewhat mitigated by standardized processes and advancement in small satellites – which has resulted in higher satellite reliability. It’s also a trend that can be mitigated by launching fleets of small satellites into a test orbit and designing them to decay in orbit should they enter orbit dead on arrival.
By launching these satellites into test orbits before relocating working satellites into LEO orbit, some of the space debris can be mitigated. But not every actor in space will be willing to play by these rules.
So, while the increased quality and reliability of small satellites – and the use of test orbits – could help to mitigate the creation of new space debris, it’s foolish to think that no new space debris will be created. And there is already space debris existing in orbit that could cause collisions – resulting in even more debris. So, what do we do about it?
Policy, technology, and cooperation
As I stated earlier, it’s foolish to think that there won’t be more space debris created in today’s congested space domain. This makes it increasingly important to try and eliminate what is already there. And that’s something that coalition governments should be talking about as a top priority for the near future.
Space has already become a warfighting domain, and today’s coalition governments and military forces don’t need the added threat to their space assets and spacecraft that is posed by space debris. But cleaning existing debris is something that will most likely have to fall to government organizations, as commercial providers simply don’t have the economic incentive to lead the charge.
Currently, it’s less expensive for commercial operators to build redundancy into satellites in anticipation of a potential collision with other satellites and space debris. It’s also less expensive to insure their satellites against collision. If insurance and redundant design are cheaper than actively working to increase orbital health through cleaning, industry simply isn’t going to take that step unless mandated.
The U.S. government is already working to mandate responsible retirement plans for satellites nearing their end-of-life. It’s working to establish treaties and agreements with other nations to be responsible actors in space. It’s also working to mandate commercial satellite operators to limit the creation of future space debris. But that may not be enough.
“Currently, it’s less expensive for commercial operators to build redundancy into satellites in anticipation of a potential collision with other satellites and space debris. It’s also less expensive to insure their satellites against collision.”
Actively working to remove existing debris is an essential step, and it’s one that governments will most likely have to take.
Another important step involves increasing situational awareness in space. This is something that commercial operators and the U.S. government are already pursuing. Today’s commercial operators – including SES – are actively working with both the Space Data Association and the U.S. Air Force Combined Space Operations Center (CSpOC) to identify potential conjunctions, evaluate the level of risk and take appropriate action when necessary to increase the separation distance.
However, situational awareness can always improve – become more trusted and more precise – to ensure that information about potential conjunctures and collisions are accurate and actionable.
By taking active steps to clean the space domain of existing debris and working with industry partners to increase the situational awareness and accuracy of the tracking and measurement of space debris, we can ensure that today’s new space age doesn’t end in tragedy, with a new, massive influx of satellites sparking a calamity of collisions.