I remember the first time I saw a satellite. I was a teenager, standing in my mildly light-polluted suburban yard and looking at the stars. The satellite was a faint “star” moving slowly and steadily across the sky, and as I looked at it I felt a mixture of awe and wonder that such a thing could be seen – and that humans could put an object into orbit at all.
It was a lifetime ago, and I now look back on that night with more discomfort than nostalgia; the naivety of my youth feels almost embarrassing.
It is because these days it fills me with dread to see one of the heavenly travelers. We are firmly in the era of satellite constellations—groups of dozens of similar satellites—and are currently entering the era of the megaconstellation, where groups of thousands of satellites swarm the sky. The clusters of satellites started small, but like a viral outbreak, they grew almost imperceptibly – and now we are dealing with a pandemic.
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I wrote about this issue before Scientific American in May 2023. At that time, there were 7,500 active satellites in Earth orbit; more than half of them were SpaceX Starlink satellites providing Internet services. In just under three years, the number of Starlink satellites alone in orbit has reached almost 10,000. Today, there are literally more Starlink satellites up there than the sum of them all other operational satellites.
This ratio will almost certainly be more skewed towards Starlink as well; back in 2019, when the first Starlink satellites were launched, SpaceX applied to the Federal Communications Commission (FCC) for up to 30,000 additional satellites.
Does that sound bad? Well, it may come one day, all too soon, as we are nostalgic for such a small number of satellites cluttering the sky. On January 30, 2026, SpaceX applied for permission to launch as many as one million more satellites.
Yes, one million.
SpaceX’s plan is for this sprawling mega-constellation to become a distributed network that acts as an orbital data center, similar to the ground-based data centers that provide the information processing backbone of the Internet. In this case, instead of having equipment capable of all that processing power stored in massive warehouses, each satellite in orbit would do a small part of the number crunching and then send the final results back to the ground.
In principle, such plans would be able to ease the insatiable power requirements and environmental effects of ground-based centres. By 2023, data centers in the US alone consumed a staggering 176 million megawatt hours of energy – a little more than 4 percent of the nation’s annual electricity consumption and enough to power 16 million homes for a year. Many of these centers are powered by fossil fuels that add greenhouse gases to the atmosphere that exacerbate global warming. These centers also need to be cooled, and they usually use large amounts of water to do so. And as the use of computationally intensive artificial intelligence increases, so will the appetite for ever more power – and the potential for ever greater environmental damage.
Exporting most of this “computer” to orbit, SpaceX claims, is how to break this vicious cycle. And there is some truth in that: the satellites will be solar-powered, which reduces the need for electricity on Earth. They also won’t need water to cool their hot chips, but instead will rely on large radiators to vent heat—a slower, less efficient method, but the best available in the near-vacuum of space. Starlink satellites currently in use already cool in this way, and the heat load for a satellite used to process data will be about the same as one used to provide the Internet, so this is not the showstopper problem many assume it is.
So if you don’t look too deep, large-scale orbital data centers might make sense. Scratching the surface of this idea, however, shows just how colossally awful it is.
First, these satellites must become to outer space. As astrophysicist Jonathan McDowell, my friend and colleague, points out, SpaceX claims that their Starship rocket can (once it passes testing) take 150 tons to low Earth orbit, but there are good reasons to believe that the real operational capacity will turn out to be more like 100 tons. Assuming that low-Earth orbit is indeed where all the satellites will go (and many will undoubtedly need to fly higher), and that they’re each two metric tons, that means Starship can launch about 50 satellites at a time — so creating this mega-constellation even under very optimistic assumptions will require something 20,000 Starship launches.
It gets worse: these satellites will fail after a few years and need to be replaced. Ultimately, maintenance of this theoretical million-satellite mega-constellation could take the size of 10 starships are launched per day, forever.
The environmental impact of all this would not be trivial. A single Starship launch releases 76,000 tonnes of carbon dioxide equivalent, for example – apart from problems with noise pollution and potential damage to nearby habitats. Twenty thousand launches would have a huge effect, including more damage to our critical ozone layer. The fiery atmospheric re-entry of satellites would also be a source of pollution, dumping significant amounts of vaporized metal and plastic into the planet’s fragile upper atmosphere. At least one Starlink satellite already burns up like this every day, based on when those satellites started entering orbit and their scheduled replacement cycles — and orbital data centers can make that reinsertion rate skyrocket.
As if this were not enough, a spread of mega-constellations also entails risks for the orbital environment itself. The volume of satellites already above our heads is enormous, but the number of proposed satellites is so large that managing space traffic to avoid collisions would become an even more extensive task. Even a single collision in orbit can be catastrophic; these satellites travel at speeds many times faster than a rifle bullet, and a direct hit from one creates a cloud of shrapnel. That debris spreads, hits other satellites and creates even more debris, resulting in a violent cascade called the Kessler syndrome. Triggering this syndrome is already a real concern, despite the fact that orbital decay naturally “cleanses” low-Earth orbit over time. Increasing the number of satellites by several thousand times could make this threat apocalyptically worse.
And as an astronomer, I can’t help but worry about the effect on my beloved field. A study published last December Nature showed that if there were approximately half a million satellites in orbit, at least one would contaminate essentially all observations taken by the Hubble Space Telescope. Ground-based telescopes will also be hard hit; they already are! Vaporized debris from reentries will also add skyglow, making it harder to see faint cosmic objects. Even simple stargazing from your garden will be affected. In a very real sense, by launching so many satellites, we risk losing the sky.
Remember, SpaceX isn’t the only one filling the sky. China has applied to launch 200,000 satellites for its own network. Other countries and companies will no doubt follow suit; Amazon and Blue Origin are already planning to launch thousands of satellites each as well. Even more worrying is a new company, called Reflect Orbital, which wants to send thousands of giant space mirrors into orbit to provide “sunlight on demand” anywhere on Earth. The rays would be far brighter than the full moon and, although gently pointed, would spread in the atmosphere to be very bright outside the beam, disturbing wildlife and effectively destroying the sky’s remaining natural beauty by erasing the stars from our view. These mirrors are a truly terrible idea.
That’s the common theme here, actually. Even ignoring the deeply disturbing environmental and light pollution from all these launches and reentries, there is another effect. Our night sky – and it is ours – is a natural wonder, a cosmic park we need to preserve, not exploit with a laissez-faire attitude. This careless exploitation of the skies above is a real danger to us all.
If all of this scares you as much as it does me, then make your voice heard. The FCC is taking public comments on Reflect Orbital’s filing until March 9, 2026, and on SpaceX’s Mega Constellation until March 6 (the day this article is published). The American Astronomical Society has more information and linksas well instructions on how to submit a comment. I did!
