Is It Time For Global Space Traffic Control?
As the space environment surrounding Earth becomes increasingly congested, the issue of managing space traffic safely, effectively and fairly needs to be addressed. Until recently, “Space Traffic Management” has been guided by a voluntary set of space operating procedure; this is the first step towards developing “Space Traffic Control”, which is the point at which lawyers become involved, and space regulations become both international and mandatory.
A recent report in the Daily Telegraph (paywall) suggests that the legal regime may soon be with us:
“Elon Musk and Jeff Bezos in star wars over plans for mega satellite constellations.”
While it is encouraging that the mainstream media are taking an interest in the subject, let’s take a somewhat closer look at some of the issues raised in the Telegraph article:-
The two moguls’ rival satellite companies, SpaceX and Kuiper, have asked US regulators to decide their claims to the same orbital territory.
It’s probably worth noting here that the law as it stands doesn’t allow any organisation, commercial or governmental, to “stake a claim” to “orbital territory”. The international treaties signed back in the 1960s and 1970s establish the space domain as a “commons” and although there is an international frequency registration process, coordinated via the ITU, to avoid interference between satellites in the RF domain, this does not confer “rights” to certain orbits. It would also be somewhat presumptive of US regulators to make any specific determination in this case, since there are plenty of other space-faring nations around the globe who might feel somewhat aggrieved if their own plans to exploit certain orbits were pre-empted by a decision in the US.
SpaceX, Mr Musk’s company, already has more than a thousand of its Starlink “microsatellites” in orbit out of a planned 12,000, and now wants to lower the orbit of around 2,800 of them in order to improve broadband speeds and lower the danger of future space debris.
It is true that lower orbits improve link budgets, and so enable improved broadband data rates. It is also true that lower orbits decay more quickly, and so reduce the debris risk. But this is emphatically not really why they’re arguing. As you might expect, in a disagreement between two of the world’s richest men, it’s all about money.
The key word missing from the Telegraph article is “latency” – the time it takes to deliver information. Financial traders will pay huge sums of money to receive data fractions of a second earlier than their rivals, and since satellite communications operate at the true speed of light, whereas fibre-optic cables achieve only about two thirds of that figure, if a satellite constellation is low enough it can “beat the cables”, despite the fact that the path length through the satellites is longer. For mega-constellations, therefore, the lower the orbit, the lower the latency, and the larger the profits – time really is money in this arena.
This is why Space X took the most unusual step of revising their orbit strategy for Starlink, since their original orbit altitude at 1200 km was too high to make an impression on the financial markets. It’s also why Amazon’s Kuiper is keen to keep them out of the lowest orbital filings. As the Telegraph article notes, they are both “satellite networks, which will beam down internet signal to some of the planet’s most remote areas.” But that isn’t where they’ll make their money. People in the planet’s most remote areas simply don’t have the spending power of Wall Street and the City of London.
Amazon’s Kuiper constellation will consist of “3,236 satellites” according to the Telegraph, which is clearly a very large number, but still quite small compared to Starlink. Both mega-constellations make Iridium’s existing global constellation (notionally consisting of 66 active satellites) look quite puny.
Why do these new networks require quite so many satellites? The answer lies in the desire to increase data rates – rather than delivering coverage to their entire footprints, these constellations focus on a comparatively small region close to their nadir position, thereby limiting the potential number of subscribers in the footprint who wish to stream videos of cats doing silly things.
And do these large numbers of low orbit satellites matter? Well, as discussed in a previous blog item, The impact of satellite operations on astronomy | GNOSIS Network they have the potential to complicate life significantly for the astronomical community. Arguably, if they are at lower altitudes, they will spend less time in twilight conditions; but they’ll be closer to the Earth, and hence appear brighter too…… More calculations are needed to establish which of these factors is most important.
Amazon and SpaceX’s dispute focuses on their differing orbital “shells”, meaning layers of space at different distances from the Earth’s surface where large numbers of satellites can orbit without crossing over.
While it is true that confining constellations to particular orbital shells below 600 km altitude would reduce the probability of inter-constellation collisions, it fails to address the potential issue of intra-constellation collisions between members of the same constellation. As this representative illustration of the Starlink constellation shows, there are many, many nodes where orbital planes intersect, and where two satellites could collide if they lose the ability to manoeuvre.
Relatively tightly defined “orbital shells”, of the sort that Space-X and Amazon are purportedly arguing about, actually increase the local density of satellite hardware and make such collisions more likely. Permitting constellations to use mildly elliptical orbits would spread the hardware over a larger volume of space, reducing both the chances of collisions, and, (in an ideal world), the insurance premiums of the operators. And at these very low altitudes, if a collision does occur, at least the debris would not take too long to re-enter the Earth’s atmosphere.
A very good article and question Stuart…. the answer of course is YES! The issue is what consideration is needed and to what the ‘Control’ should cover?
All artificial satellites and orbital ‘space junk’ but most notably Low Earth Orbit objects have had an impact on both space and Earth domains. And things are rapidly changing. It should not be forgotten that in the last few years light and radio interference has an increasingly negative impact on astronomy, the continuing launch of megaconstellations are likely to make ground based astronomical observation (both optical and radio) difficult and maybe ultimately impossible! The irony of this is of course is that without the oldest and noblest of the sciences astronomy, satellites, both unmanned and manned space craft would not be possible… Commercial exploitation of LEO may very well kill its parent and enabler!
It should also be worth noting that another threat from deorbiting (naturally, intentionally or accidental) of the huge numbers of future LEO megaconstellations will ‘seed’ the upper atmosphere with aluminium particulates that affect global climate. Recent studies have indicated that only small amounts of aluminium particulates can impact negatively and disproportionately on climate change.
For example, Starlink satellites have a dry mass of about 260 kg… 12,000 satellites will total 3100 tonnes… A 5-year cycle would see on average almost 2 tonnes re-entering Earth’s atmosphere daily. While small compared to the 54 daily tonnes of meteoroid mass, the satellites are mostly aluminium, most meteoroids, in contrast, contain less than 1% Al by mass. Depending on the atmospheric residence time of material from re-entered satellites, each megaconstellation will produce fine particulates that could greatly exceed natural forms of high-altitude atmospheric aluminium deposition, particularly if the full numbers of envisaged satellites are launched. Anthropogenic deposition of aluminium in the atmosphere has long been proposed in the context of geoengineering as a way to alter Earth’s albedo. These proposals have been seen justifiably as scientifically controversial and even past controlled experiments encountered substantial opposition. Megaconstellations will begin this process as an uncontrolled experiment!!! Remember the current projected increase in FCC approved licenses for Starlink are likely to increase this amount proportionately… Then there are other commercial and governmental constellations to consider, if the current predictions of 100,000+ total LEOs by 2030 prove correct, the Earth will be in real trouble!
This is but just Two of the issues to be taken into account for the issue of “Is It Time For Global Space Traffic Control?”… others such as cultural and religious impacts for those who treat the night sky as sensitive are yet another can of worms to tackle! So again, the answer to your question is YES!
For me the ONLY way to do this would be to have Global Policy and Control, this should be done under the auspices of the United Nations and its Agencies. Currently the ITU (International Telecommunication Union) and UNOOSA have any ‘semblance’ of global control, BUT their oversight is limited and very defined. There is a NEED for a new and ‘all-encompassing’ purview and regulatory control UN Agency that looks at orbital safety, scientific, commercial, economic, technical, environmental, legal, sociopolitical and cultural impacts (maybe others?) of the use of Space.
Until this is discussed, agreed and a Global Policy and regulatory framework put in place, I believe that an immediate Global moratorium needs to be imposed on further Commercial megaconstellation launches… Not something I would imagine a lot of people (especially the corporates) would like to see? But the protection of rights of the global citizen when it comes to the sky over their heads need to be respected and protected…. Any failure to do this risks the wrath of the world!