Humans have always looked to the stars: they have built their calendars and cultures around the night sky and found inspiration and information in its patterns. Searching the skies as they always have, people are now faced with an expanse clouded with light and satellites—straining to glimpse what their ancestors may have seen.
A piece of space junk has, for the last seven years, been circling the Earth and Moon, getting pushed and pulled around by their respective gravitational forces. The journey has been so unpredictable that some scientists have described it as “chaotic.” But its turbulent trip is now being brought to an abrupt end as the piece of space junk is expected to crash into the Moon on Friday, March 4, 2022.
The news is by no means small. The piece of old space junk, which was originally thought to be from SpaceX but is now understood to originate from an old Chinese rocket, is 12 meters long and weighs four tons. It’s also moving at a rate of roughly 5,600 miles per hour. While the damage caused by the crash is unlikely to have a significant impact on either the Moon (or the Earth), the incident has sparked renewed conversations about the amount of junk floating in space—and what to do with it. For context: over 27,000 pieces of orbital debris is currently being monitored by the U.S. Department of Defense’s global Space Surveillance Network (SSN). The number of space junk items that are too small to track is much higher.
Read on for a story by Joshua Sokol about the environmental, cultural and, even, aesthetic repercussions of space pollution.
Last July, during the Perseid meteor shower, I took a three-hour drive and a two-hour ferry ride to Ocracoke, North Carolina, a barrier island far off the Atlantic coast, where the pirate Blackbeard died.
I left my tent at 1 a.m., brushed off mosquitoes, and clambered over dunes to the empty beach. How can I convey how dark it was? The path of the galaxy burned across the sky, and when I cupped a bit of surf in my hands, more stars glinted back up from the water. Places like this are caught between light pollution pushing out from mainland cities and sea level rise squeezing in from the ocean. But for now, satellite images say that Ocracoke boasts some of the darkest night skies left in the entire eastern United States.
This vanishing experience is at the root of human calendars, spirituality, and science. Stargazing used to be the extent of space travel. But over the last six decades, we have begun to venture up in other ways—sometimes for grand, universal human purposes; other times for the sake of jingoism, commerce, patronage to particular congressional districts, the profit margins of defense contractors, and tourism advertising. Regardless, each of these activities has left a little bit of us behind.
On the moon: scattered ashes of the scientist Eugene Shoemaker (a tribute according to NASA, the profanation of a sacred place according to the Navajo Nation). A capsule of dehydrated tardigrades spilled from a failed Israeli lander. Human shit.
On Venus, Mars, and more: the power-drained husks of all the old probes that landed. Wreckage from the ones that didn’t.
Orbiting Earth and farther afield: at least 23,000 stray objects as big or bigger than a grapefruit. Glittering mylar scraps. Shards from satellites destroyed in space weapons tests conducted by the U.S., Russia, China, and India. A red Tesla Roadster. More shit.
Aeronautics researchers, NASA, and the U.S. Space Force think about this as a problem of space debris, amenable to policy tweaks and engineering fixes. In this framing, near-Earth space is big and potentially useful but also finite.
Junk high above our planet’s atmosphere can zoom around on frictionless tracks for centuries, moving fast enough to shatter anything it hits into pieces that themselves become potential bullets. “Stuff that we put up there can stay up for a very long time,” the space debris researcher Hugh Lewis told me. “The space environment has a memory.”
“Stuff that we put up there can stay up for a very long time. The space environment has a memory.
Today, he says, the frequency of near-misses in space is rising, as is the risk of outright collisions. In 2009, for example, a commercial satellite and an abandoned Russian military satellite slammed into each other at over 22,000 miles per hour, an explosive event that left thousands of new shards of shrapnel in its wake. More wrecks like this will make huge swaths above our planet more and more hostile to satellites or human travelers. That could hurt scientific satellites—for example, the ones that monitor climate change—endanger astronauts, and block all those nations that haven’t yet kicked off their own space programs but might want to. Or, we could prevent future catastrophes while cleaning up past mistakes. That could involve tightening regulations on space launches, implementing tighter tracking procedures to avoid collisions, and starting to sweep up—which several space startups have already begun promising they’ll do.
But perhaps we should also think about space trash as a cultural, even an aesthetic, issue. Human societies have always been star-smitten. Consider our weekdays: a day for the Sun, a day for the moon, and five days for five gods linked in turn to the five wandering stars of Mars, Mercury, Jupiter, Venus, and Saturn. In the calendar of my own faith, Judaism, the names of months were taken from the ancient Babylonian astronomical calendar, and the Sabbath day only ends when you can spot at least three stars shining at dusk.
This is by no means unique. The world is full of astronomies. Cultures around the world tell stories about Seven Sisters in the Pleiades star cluster, for example, even though only six stars are currently visible. But there were seven Pleiades stars visible in the sky 100,000 years ago, a team of astronomers argued in 2020. Our ancestors could have seen them in the early days of humanity, then carried the Seven Sisters story as humans spread to every continent, holding onto the original even as one star ceased to be visible. All of the different modern versions might have sprouted from the same source at the root of humanity’s now world-spanning tree.
Even today, in some tribal groups and families in the Torres Strait between Australia and New Guinea, for example, claims on land ownership often extend into the sky overhead, Duane Hamacher told me. Hamacher, a cultural astronomer in Australia, argues that light pollution, by blocking the stars, is a form of ongoing colonization. “When a culture has its laws and traditions written in the stars and you erase that, you’re taking [those laws and traditions] away.”
I had come to Ocracoke to get away from light pollution, but I was also on the lookout for another, newer form of technological intrusion. Since May 2019, when the rocket company SpaceX began launching a swarm of Starlink satellites engineered to beam down internet service (Starlinks may one day number up to 42,000, a vast increase over humanity’s roughly 2,000 total satellites in orbit when they began), astronomers and dark-sky environmentalists have worried about corporate satellites in unprecedented numbers eventually outnumbering real stars in the sky.
“When a culture has its laws and traditions written in the stars and you erase that, you’re taking [those laws and traditions] away.”
These satellites aren’t themselves trash—at least depending on your views of SpaceX founder Elon Musk—although any inadvertent accidents between them and other space objects could quickly produce some. Their sheer numbers may contribute both to the space debris problem and to a new kind of visible light pollution shining down from both active satellites and abandoned refuse.
Granted, Lewis says that SpaceX has been proactive in addressing the pollution its own actions threaten to accelerate. For example, the current Starlinks are roughly one third or one quarter of the brightness of the original satellites launched in 2019, as I previously reported in Science, making them difficult for human eyes to see (albeit not as dim as astronomy researchers want). And rather than risk them breaking down and lingering in orbit after their missions end, SpaceX has begun steering the satellites down to burn up in the atmosphere. But these kinds of mitigations are not required by national and international law, and it isn’t clear how future Starlinks and other competing corporations will behave.
These varied types of space pollution are more related than it might seem. In a 2021 study, light pollution researchers calculated that sunlight was already scintillating off the current population of active and derelict space objects as well as scraps of shiny metal trash. Even before SpaceX and other satellite builders began pumping big, new spacecraft into orbit, the objects already there were adding 10% more background glow to the darkest skies on the planet, they estimated. Other threats are emerging, too: if tens of thousands of satellites really do launch and eventually burn up above Earth as a supposedly eco-friendly disposal technique, they could add extra aluminum to the upper atmosphere, potentially interfering with its chemistry.
On Ocracoke, I watched the skies like a hawk, half-hoping for the odd satisfaction of satellites crossing my view as they had on other nights before. But this time, I didn’t see anything.
Eventually, sated with the view and the real meteors, I went back to my tent. When I woke up, the sun was already beating down, other campers were heading down to the beach with umbrellas, and I found that no matter how hard I tried, I couldn’t quite remember how things had looked the night before.