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Mega-Constellations Pose Massive Risks to Shared Space Access

Space is getting cluttered, and we need to be talking more about it.

Over the past decade, the costs associated with building and launching spacecraft have vastly diminished, and the result has been increased access to space—often with deleterious repercussions. The industry is trending toward mega-constellations of smaller, cheaper, and economically expendable satellites, the chief example being SpaceX, which has been launching Starlink satellites in large batches since 2019. SpaceX’s ultimate goal is to create mega-constellations consisting of thousands of satellites, and that company isn’t alone in its space-conquering aims. The alarming result of this short-sighted bludgeoning of Earth’s atmosphere is that we’re quickly entering a new era of orbital danger.

“What’s happening today,” says John Janka, Chief Officer, Global Government Affairs and Regulatory, Viasat, “is very different in both scale and scope than the risks that have ever existed with the commercial use of space.”

Types of Space Risk

Risk is the paramount concern behind the rise of mega-constellations. Viasat sees three main categories of risk: potential collisions, access to shared space, and environmental issues on Earth.

Collision risk. There’s a lot of junk floating around in space. “Did you ever see the movie Gravity?” asks Janka. “That’s the kind of thing we’re talking about. Stuff gets launched into space, parts fall off, an astronaut drops a wrench, and sometimes satellites collide with each other.” As suggested by the Kessler Syndrome, posited back in 1978, a piece of debris the size of a softball might take a decade or more to fall out of orbit, and in the meantime it’s bashing into other things, creating more debris and exponentially more risk over time.

Collisions in space can be like a bomb going off, thanks to speed and kinetic energy. Worse, the resulting debris can travel hundreds of kilometers, creating vast shrapnel fields that satellites must try to avoid. “The best way to avoid collisions,” says Janka, “is to make sure satellites are maneuverable. Satellites have control mechanisms and propulsion mechanisms, but maneuverability only works as long as all the satellites’ systems are working. If your satellite isn’t reliable, you’re increasing the risk of collisions.”

The satellite industry was once home to industries that were rigorous about their approach to space. These companies were meticulous about safety because it was very expensive to build satellites and get to space. They had a natural incentive to make everything function correctly and withstand the test of time.

“But because the cost of access to space has dropped dramatically,” says Janka, “people are willing to launch satellites with parts that aren’t space-qualified. There’s a real movement toward the Silicon Valley ‘fail-early-and-often’ mentality: It’s cheap, so we’ll just throw it up there, and if it breaks, we’ll put more up there because they’re expendable. That philosophy works OK on Earth—but not so great in space, where it creates a bunch of dangerous trash that you can’t clean up.”

Shared access. For many years, access to space occurred on a shared basis. There were many look angles available in space; one satellite might use radio spectrum in one direction, and another satellite might be located at a different point in space using the same spectrum in another direction. Both systems could coexist.

“Imagine looking up at the sky, and envisioning it as a honeycomb,” says Janka, “and every cell is a possible place where somebody can use spectrum. There are so many honeycombs and so few satellites that there’s room for a lot of traffic. That’s how we coexist, both from a radio frequency perspective and from the viewpoint of physical orbits. Space is big. If everyone stays in their lane, there’s room for lots of people.”

Mega-constellations pose a gigantic problem to this harmony, hoarding all the good-look angles in the sky, and the result is that there’s no longer much room to use the same spectrum anymore. Janka equates this behavior to vehicles swerving across all 10 lanes of a superhighway. “Instead of staying in their lane,” he says, “they’re wandering across the freeway without any regard to everyone else in their lanes.”

And this phenomenon is already happening on an unprecedented scale. The more one company puts satellites up at a certain range, the less room there is for anyone else. As Jonathan McDowell said, “the grabbing-up of all the good territory is a reasonable complaint.”

Environmental issues on Earth. In late 2020, the Aerospace Corporation released a report called “Environmental Impacts of Satellites from Launch to Deorbit and the Green New Deal for the Space Enterprise,” expressing concern that when mega-constellations of satellites reach the end of their lives, they de-orbit and intentionally vaporize into particles in the atmosphere, creating what has been described as a complex zoo of chemicals that includes aluminum oxide.

“Thousands of satellites will be doing this each year now!” Janka says. “It’s not like a small bonfire in a back yard; it’s more akin to a huge forest burning. And no one is thinking about it. We need to study this problem because the pollution coming down from above is much worse than the pollution coming up from Earth. It can also impact climate change because of something called ‘radiative forcing’ and negative effects to the ozone layer.”

There’s also the notion of disrupting the “dark and quiet sky.” From the perspective of Earth-bound observers, the night sky is important for scientific research through optical and radio-based astronomy, for astrophotography, and simply for people who enjoy stargazing. “We’re talking about an issue of scale,” says Janka. ”When thousands of satellites are creating trails across the sky, that produces visual and radio interference, and it’s going to be an increasingly big problem going forward.” For more about the pollution of the night sky, see Losing the Sky, by Andy Lawrence.

The State of Shared Space

As the unchecked rise of mega-constellations begins to endanger safe, equitable access to space, what’s happening behind the scenes?

“There are existing risk-mitigation guidelines that are designed for the launch of a single satellite,” says Janka. FCC regulators have historically insisted that a single satellite’s probability of colliding with another large (10 cm or larger) object in space remain below one in a thousand (i.e., .001 percent) over its mission life. “That works fine if you’re putting up one or ten satellites, but nobody has ever put up a constellation of thousands of satellites.”

What’s being considered—and some of which is already occurring—is the launch over the next decade of 10 times as many satellites as have been launched over the past seven decades.

“We’re seeing proposals to put up 4,400, 7,500, even 30,000 satellites into orbit,” says Janka. “One operator, if they have their way, will put up 42,000 satellites that have a 5-year lifespan—or 120,000 satellites over 15 years. You can scale the risk. Somebody needs to look at the total risk associated with these kinds of constellations on an aggregated basis and make sure it stays at a reasonable level. Risk increases with the number of satellites.”

It’s a matter of technology far outpacing the law. And that’s a very dangerous prospect when you’re talking about space.

“Not to make light of concerns on Earth that result in unwanted effects—polluting rivers, for example—but it’s a heck of a lot easier to clean up Earth than it is to clean up space,” Janka says. “It’s time for regulators to provide new guidance, for the simple reason that many people don’t often have the incentive to do the right thing. Unless there’s suitable guidance from regulators, industry will fill that void. There’s a huge risk that all of space could be adversely affected by the irresponsible actions of one party that has no incentive to look out for others.”

In 2018, and again last year, the FCC recognized the necessity for new rules that anticipate the orders-of-magnitude increases in satellites being proposed. The new rules—not yet resolved—suggest taking a “total system” approach, emphasizing that the entire mega-constellation must adhere to the same .001 probability of colliding with another large object in space. However, in response to the new proposed FCC rules, a few aggressive industry players pitched a fit, complaining of a lack of fairness. So, the FCC paused its deliberations, promising to look more closely at the situation and opening up the regulatory process to further comments. 

“To our satisfaction,” said Janka, “a number of influential people in the industry have weighed in—including satellite manufacturers such as Maxar and Boeing—and they’ve agreed that mega-constellations represent an urgent concern and that something needs to be done.”

What’s Next?

The satellite industry is facing a fork in the road. The overriding question is how the players in the industry are going to manage the problem posed by mega-constellations both nationally and internationally. Considering the intricacies of the world’s various regulatory bodies, how are we going to ensure that space junk doesn’t become so big a problem that it’s unsolvable?

As far as the United States is concerned, there’s reason for optimism in the change in national leadership and President Joe Biden’s selection of Jessica Rosenworcel as acting chairwoman of the FCC.  Rosenworcel has strong and well-informed views on the topic, and she understands that the use of space is fundamentally changing. In fact, last year, Rosenworcel expressed concern that the proposed rules did not adequately deal with collision risks for large constellations and that “going forward we need to prepare for the future with more speed and urgency if we want to retain our global authority in space matters.”

“She has a history of being thoughtful and responsible,” Janka says. “Smart money is that the new administration will examine things through a science-backed lens and provide a fresh look at what’s been going on.” 

We have to act quickly, and we have to act now, because a failure to manage the meteoric rise of space collision probabilities could deny everyone access to space for decades to come.

The editorial staff had no role in this post's creation.