Space junk is out of control. Here’s why — and what to do about it.
Since the Soviets launched the first satellite in 1957, humans have put tens of thousands of objects in Earth’s orbit.
Each dot represents one of 9,000 satellites orbiting the Earth. They enable modern necessities such as cell phone signals, GPS and high-speed internet.
About 25,000 are pieces of obsolete satellites, rocket parts and debris — space junk orbiting out of control and posing a threat to the satellites people need.
Nine in 10 useful satellites are located in an area called low Earth orbit — as is most of the junk. Objects in this zone move at about 17,000 miles per hour, making it hard to avoid collision.
The word “space” implies a lot of it: a near-infinite expanse of emptiness above the atmosphere of this crowded planet. Yet it turns out that the orbits along which rockets fly and from which satellites beam internet connectivity to Earth are a limited resource — and they’re becoming more crowded every day.
The Federal Communications Commission last month issued the first-ever fine for what’s known as space junk, against the Dish Network. The satellite television company failed to dispose properly of one of its satellites, leaving it at a lower orbit than it promised when securing its license. What’s remarkable isn’t the transgression, but the penalty. Today, countries and companies alike sending objects into space are mostly held to standards lower than the average kindergartner. They’re allowed to make a mess, and they’re not really required to pick up after themselves.
About 8,000 active satellites move through low Earth orbit. Their trajectory can be adjusted from Earth to avoid collision.
But tens of thousands of large pieces of junk orbit out of control in the same area. Some are as big as a school bus.
The United States, Russia and China are responsible for 80 percent of the debris.
Less than 10 percent of the junk is large enough to be tracked. NASA estimates that there are an additional half a million smaller pieces of debris in space. Even a penny-sized object could disable a satellite.
Some space junk was discarded during missions; maybe an astronaut dropped her lucky penny, or released an instrument’s camera cover after it was no longer needed. Others, however, are the result of collisions: Even that lucky penny, traveling at 15 times the speed of a bullet, can cause catastrophic damage — ending a satellite’s mission or, worse, splintering that satellite into fragments. Scientists estimate that there are more than half a million tinier particles hurtling through space, each with the ability to do serious damage.
Bigger collisions, naturally, cause bigger clouds of debris. Many of these “breakup events” are accidental. Some, however, occur on purpose. China obliterating one of its Fengyun weather satellites resulted in approximately 3,000 trackable bits of debris, 2,700 of which are still in orbit, according to space traffic firm LEO Labs. Experts estimate there may be 32,000 other fragments too small to detect. Rocket bodies that explode accidentally as they float through space after detaching from their payloads cause similar problems. The key is to eject any residual fuel as soon as possible; too often, that doesn’t happen.
Every collision makes the next collision more likely. The addition of even a single piece of debris to an orbit gives the other objects flying through it another thing to run into — and a crash can spawn thousands. This phenomenon of exponentially growing risk is known as Kessler syndrome. Donald Kessler, the man who predicted it, warns that eventually the tiniest fragments will collide with the tiniest fragments, until space is filled with subcritical particles wreaking constant havoc.
That’s obviously bad news for satellites. As many as 1,100 are expected to launch every year by 2025, up from just 365 in 2018.
The solution isn’t to demand the launch of fewer satellites; these bring real benefits to people globeside. And while traffic management is certainly necessary, pieces of garbage are never going to be able to follow even the most sensible rules of the orbital road. That means two things need to happen: People need to stop littering, and they need to take out some trash.
The professionals, unsurprisingly, have more carefully considered names for these processes — mitigation and remediation. Any time a company (or a country, for that matter) wants to put a satellite in the sky, it should have a clear plan for the instrument’s end of life. For objects in very high geostationary orbit, this usually involves sending the item to the out-of-the-way “graveyard” orbit. For objects lower down, it tends instead to involve moving them lower still, so that they will burn up upon reentering the atmosphere.
The United Nations agreed in 2007 to a set of guidelines recommending disposal no more than 25 years after a satellite’s mission ends. The FCC’s recent rule shrinking this window to a mere five years is more sensible; sooner would be better. The Federal Aviation Administration has jurisdiction over the upper-stage rocket bodies also cluttering orbits. A proposed rule requires that commercial operators dispense with these launch vehicles safely — but hews to the 25-year standard.
Ideally, anything that goes into space should come down as soon as possible. Vessels should be designed to avoid leaving detritus — like those camera covers — as well as for easy removal. Rules should mandate the venting of any spare explosive fuel. Destructive antisatellite tests should be banned.
Active removal of debris that has failed to get out of the way is technically tricky, but at least for large objects, remediation is possible. Encouragingly, some countries are beginning to try. The European Space Agency is working on a spacecraft with arms that simulate a Venus’ flytrap to snatch derelict bodies out of orbit. The Defense Department’s Orbital Prime program is developing technology of its own. A bipartisan bill introduced by Sen. John Hickenlooper (D-Colo.) that passed the Senate last year would jump start a similar program. Figuring out how these tools might repair or repurpose defunct spacecraft would also pay dividends; so would raising a recyclable satellite industry.
No nation, however, can save space on its own. It took multiple great powers to create this clutter, and now cooperation will prove essential to clearing it. A global convention to set a 21st-century code of conduct for space is in order. Existing treaties, forged in the 1960s and 70s, can sometimes do more harm than good: Unlike on the sea, in space no nation is allowed to touch another nation’s object, no matter if it is dead and needs removing. New treaties could help ensure that, instead, countries pitch in to do exactly that — purge the planet’s orbits of junk, no matter where it came from. And, of course, they could limit the amount of garbage that makes it into orbit at all.
There is no reason, other than carelessness, that humanity must run out of space in space. Time for the whole world to clean up its room.