I remember the first time I saw a satellite. I was a teenager, standing in my slightly light-polluted suburban yard and stargazing as usual. The satellite was a faint “star” moving slowly and gently 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 look back on that evening now with more disappointment than nostalgia; my adolescent naivety is almost embarrassing.
That’s because, these days, seeing one of these celestial travelers scares me. We are firmly in the era of the satellite constellation – groups of dozens of similar satellites – and are currently entering the megaconstellation era, in which groups of thousands of satellites take over the sky. Satellite groups started small, but, like a viral epidemic, they grew almost without us realizing it – and now we are facing a pandemic.
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I wrote about this problem for Scientific American in May 2023. At the time, there were 7,500 active satellites orbiting Earth; more than half of them were SpaceX Starlink satellites providing internet service. In just under three years, the number of Starlink satellites in orbit reached almost 10,000. Today, there are literally more Starlink satellites up there than the sum total of all other operational satellites.
This ratio will almost certainly also become more skewed in favor of Starlink; In 2019, when the first Starlink satellites were launched, SpaceX filed an application with the Federal Communications Commission (FCC) for up to 30,000 additional satellites.
Does this look bad? Well, it could be that one day, too soon, we will be nostalgic for such a small number of satellites cluttering the sky. On January 30, 2026, SpaceX requested authorization launch up to a million additional satellites.
Yes, one million.
SpaceX’s plan is for this sprawling mega-constellation to become a distributed network operating as an orbital data center, similar to the ground-based data centers that form the information processing backbone of the Internet. In this case, instead of having equipment capable of storing all that processing power in huge warehouses, each satellite in orbit would perform a small portion of the calculation and then transmit the final results to the ground.
In principle, such projects could alleviate the insatiable energy demands and environmental effects of ground centers. In 2023 data centers in the United States only consumed a staggering 176 million megawatt hours of energy, just over 4% of the country’s annual electricity consumption and enough to power 16 million homes for a year. Many of these centers are powered by fossil fuels which release greenhouse gases into the atmosphere that worsen global warming. These centers also need to be cooled and typically consume 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 risk of ever greater environmental damage.
According to SpaceX, exporting most of this “computing” into orbit is the way to break this vicious cycle. And there is some truth to this: the satellites will be powered by solar energy, which will reduce the demand for electricity on Earth. They also won’t need water to cool their hot chips, but will instead rely on large radiators to carry away the heat – a slower and less efficient method but the best available in the near-vacuum of space. Starlink satellites currently in use already cool this way, and the heat load of a satellite used to process data would be about the same like the one that provided the internet, so it’s not the major problem that many people assume.
So if you don’t look too deeply, large-scale orbital data centers might make sense. However, scratching the surface of this idea shows how colossally terrible it is.
First, these satellites must get towards space. As astrophysicist Jonathan McDowell, my friend and colleague, points outSpaceX claims that its Starship rocket can (upon successful testing) deliver 150 metric tons to low Earth orbit, but there is good reason to believe that the actual operational capacity will turn out to be closer to 100 metric tons. Assuming that low Earth orbit is actually where all the satellites will go (and many will no doubt have to fly higher), and that they each weigh two metric tons, that means Starship can launch about 50 satellites at a time, creating this mega constellation even under very optimistic assumptions would require 20,000 Starship launches.
Worse still: these satellites will break down after a few years and will have to be replaced. Ultimately, maintaining this theoretical million-satellite megaconstellation could take the order of 10 Starship launches per day, forever.
The environmental impact of all this would not be negligible. A single Starship launch emits 76,000 tonnes of carbon dioxide equivalentfor example, not to mention the problems of noise pollution and potential damage to neighboring habitats. Twenty thousand launches would have an immense effect, including even more damage to our critical ozone layer. The flaming atmospheric reentries from satellites would also be a source of pollution, spilling significant amounts of metal and plastic sprayed in the fragile upper atmosphere of our planet. At least one Starlink satellite is already burning like this every daydepending on when these satellites began entering orbit and their planned replacement cycles – and orbital data centers could cause this re-entry rate to skyrocket.
As if that were not enough, the proliferation of megaconstellations also leads to risks to the orbital environment itself. The volume of satellites already overhead is enormous, but the number of proposed satellites is so vast that managing space traffic to avoid collisions would become an even more massive task. Even a single collision in orbit can become catastrophic; these satellites move at speeds several times that of a rifle bullet, and a direct hit from one of them creates a cloud of shrapnel. This debris spreads, hitting other satellites and creating even more debris, resulting in a violent cascade called Kessler syndrome. The onset of this syndrome is already a real concern, even though orbital decay naturally “cleans” low Earth orbit over time. Multiplying the number of satellites by several thousand could make this threat even more apocalyptic.
And as an astronomer, I can’t help but worry about the effects on my beloved field. A study published last December in Nature showed that if there were about half a million satellites in orbit, at least one would contaminate essentially every observation taken by the Hubble Space Telescope. Ground-based telescopes would also be seriously affected; they already are now! Sprayed debris from re-entry will also add to the glow of the sky, making it more difficult to see faint cosmic objects. Even simple stargazing from your backyard would be affected. Concretely, by launching so many satellites, we risk losing the sky.
Keep in mind that SpaceX isn’t the only one taking over the skies. China has applied to launch 200,000 satellites for its own network. Other countries and companies will undoubtedly follow this example; Amazon and Blue Origin already also plan to launch thousands of satellites each. Even more worrying is a new company, called Reflect Orbital, who wants to launch thousands of giant space mirrors into orbit to provide “sunlight on demand” anywhere on Earth. The beams would be much brighter than the full moon and, even if carefully aimed, they would scatter through the atmosphere to become very bright off-beam, disturbing wildlife and effectively destroying the remaining natural beauty of the sky by blotting the stars from our view. These mirrors are a really terrible idea.
That’s actually the common theme here. Even ignoring the deeply worrying environmental and light pollution caused by all these launches and reentries, there is another effect. Our night sky – and it East ours is a natural wonder, a cosmic park that we must preserve and not exploit with a laissez-faire attitude. This careless exploitation of the skies poses 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 accepting public comments on the Reflect Orbital filing until March 9, 2026, and on SpaceX’s Megaconstellation until March 6 (the day this article was published). The American Astronomical Society has more information and linksas well as instructions on how to submit a comment. I did it!