SpaceX wants to launch a million satellites. Here’s how that can affect the atmosphere and night sky
Most of humanity has a good tendency to think in the short term, but often, long-term considerations – air pollution, deforestation and emissions, for example – are just not our thing.
That’s why scientists are so worried about SpaceX’s latest proposal to launch a million satellites – data centers – into orbit around the Earth.
Their concerns range from the loss of the natural night sky, to the loss of access to space, to the impact of nature on our atmosphere.
Currently, there are approx 16,000 satellites orbit the Earth14,000 of them are active. SpaceX is responsible for this more than 8,000 of them.
That number changes every week as both companies launch satellites – where they burn in our atmosphere – and sends more. On average, the company launches more than a dozen satellites twice a week.
Orbital nature
SpaceX officials have said they would like to see more than 40,000 of these Starlink satellites in orbit. Satellites provide Internet connectivity to all parts of the world, even the most remote areas.
But that’s a lot of stuff in space, and it doesn’t even take into account the more than 140 million pieces of space debris ranging in size from one millimeter to 10 centimeters. All of these things threaten astronauts in space, as well as the satellites we rely on for instruments like GPS.
That’s why adding a million more satellites into orbit is amazing.
“We’ve seen this change from thousands of satellites to 10,000 satellites especially with SpaceX. And we were very concerned about maintaining a healthy orbital environment for that,” said Aaron Boley, co-director of the Outer Space Institute and professor in the department of physics and astronomy at the University of British Columbia.
“This goes beyond just that. And by almost every metric we can think of, this is a bad idea for our long-term use and access to space.”
Images from the University of Western Ontario and Defense R&D Canada show space debris from the SpaceX Starlink satellite lighting up the night sky.
SpaceX has submitted its one millionth satellite proposal to the US Federal Communications Commission (FCC), citing the need for data centers that will not impact the environment here on Earth. For example, they say that rotating data centers won’t need to use water to cool themselves, and they note that the sun will provide them with near-constant power.
Public comment on the plan closed Friday. As of this writing, it was more than that 1,000 commentsmost of them are asking the FCC not to proceed.
Another threat to our space
OK, so what’s the big deal with having so much stuff in space? Space is big after all, isn’t it?
It’s about those long-term consequences that we think negatively about.
Scientists are worried because a lot of evidence shows that rocket explosions affect our atmosphere by putting black carbon or soot in the air, which creates a warming effect that could increase threats to our ozone layer.
Eloise Marais, professor of atmospheric chemistry and air quality at University College London, has been working track releases from both startups and reinstalls. He is concerned that we are not discussing the potential implications of the thousands of rockets needed to launch those car-sized satellites into space.
“And what are the additional effects of that?” he asked. “Because it’s really a mixture of these pollutants that affect the atmosphere.”
The main difference between these pollutants and those produced by humans at lower levels is that the launch puts them directly into the atmosphere.
Recent studies have shown that when satellites reach the end of their lives and burn up on reentry, they leave behind metals such as aluminum and lithium.
The results of this are not yet known. But that’s what worries scientists.
“It’s scary because we do this kind of climate testing without really knowing what the outcome will be,” said Marais.
In its FCC filings, SpaceX said it will “minimize any atmospheric impacts resulting from the launch of a large number of spacecraft.” No further details have been provided, however, the company says it will move some of its data centers into a heliocentric orbit (around the sun).
That’s good, since a group of astronomers, including Dark Sky Consulting founder John Barentine, estimated that if each of SpaceX’s million satellites were to be launched, it would mean one satellite entry every three minutes.
Access to space
Most people probably don’t think about how often they use satellite communications. But that Instagram post you made? He used a satellite. Looking for directions to your friend’s party? He used a satellite. Tap to pay for that Starbucks latte? He used a satellite.
We use satellites every day in many ways, and the more there are, the more dangerous the use becomes because there is a greater risk of satellite collisions.
Satellites also threaten the way we see space. We already know that satellites affect professional observatories, both visually and in terms of the electromagnetic radiation they emit. That creates noise, which can interfere with observatories that rely on radio waves.
SpaceX’s FCC filing claims that the satellites will be at an altitude of anywhere from 500 to 5,000 km. That would affect not only ground-based observatories, but also space-based ones like Hubble.
For novice and casual observers alike, this means the lights that often dot our night sky. Look up on any night and you’re bound to see a satellite crossing at some point, even over a city. In dark sky areas, it’s even worse, as the bulk is visible at night.
Astronomers warn bright light and electromagnetic radiation from thousands of Starlink satellites could interfere with ground-based telescopes like the Vera C. Rubin Observatory, limiting our study of the universe.
“We have some more detailed simulations that we will include in our comments to the FCC that suggest there could be thousands of them lit up at any given time, visible in the night sky, that would be bright enough for people to see,” Barentine said.
This loss of the night sky, something that has guided humanity since the beginning of time and influenced culture, religion and science, could not be measured.
Barentine also noted that there’s more they don’t know, since SpaceX didn’t provide much technical information in its FCC filing.
The company was trying to work with the International Astronomical Union and the Center for the Protection of Dark and Quiet Sky, in an effort to reduce the brightness of its satellites, but their proposal to launch a million satellites shocked astronomers.
“I don’t think there was anything done in secret, but it feels like a rejection of the grace that we’ve cultivated with them over the past few years, to propose something, which seems to be inconsistent with everything we’ve been talking about with them,” said Barentine.
SpaceX is not the only company proposing to launch a large number of satellites.
Jonathan McDowell, an astronomer and space sustainability analyst who tracks all launches around the world, estimates that proposals from companies and countries (including China’s two megaconstellation projects) make 1.7 million satellites.
Now, it’s possible that many of these proposals will not happen, but even half of that number would mean a lot of things in orbit. And that has ramifications for everyone.
“Even when you go to dark places around the Earth, away from your urban or urban environment, the sky will not be as dark as it was. And there will be no escape from that,” said Boley, co-director at the Outer Space Institute.
“It’s really a global effect. So this implementation affects everyone.”
