A steady accumulation of man-made debris has many calling for action.
There’s a biblical expression, though it isn’t in the Bible, that goes ‘sin begets sin.’
Well, in space, the sin is junk. Tens of thousands of orbiting objects, from old rocket parts and failed satellites to empty fuel tanks and discarded lens caps.
This litter hurls very fast through space, posing a risk to both working satellites and spacecraft, which when struck, beget more debris.
The posterchild for this came February 10, 2009, when 500 miles above the surface of the Earth, somewhere over Siberia, a telecommunications satellite, owned by a Virginia company, was minding its own business.
“It was happily orbiting along, and suddenly an old dead Russian communication satellite came at it from the side,” says Jonathan McDowell with the Harvard-Smithsonian Center for Astrophysics.
Cosmos 2251, 2,000 pounds of outdated military might, blind-sided Iridium 33, crashing at a speed north of 20,000 miles per hour.
“Suddenly, the radars didn’t see two satellites anymore. They saw thousands of pieces of small shrapnel,” says McDowell. “That was really the first major accidental collision that we’ve had in space.”
The collision created 2,200 pieces of new debris, in a neighborhood of space already crowded with both working and defunct satellites.
“It was really a wake-up call for everybody to realize, hey, the time is now, we need to do something different,” says Donald Kessler, a retired NASA scientist.
In 1978, Kessler published a research paper detailing how each collision increased the chances for more collisions, like a slow-motion domino effect. He cautioned that by the next century– meaning this century–we may be looking at a very dangerous belt of debris.
“It becomes a self-perpetuating mechanism,” says Kessler. “Right now, if we were never to put anything else in Earth orbit, the debris environment would continue to increase because you would create more fragments than would re-enter by natural decay.”
This idea, which became known as the Kessler Syndrome, caused a stir at the time, though his bosses at NASA were not immediately impressed.
“The problem for me was, I wasn’t asked to do this work, and consequently, my immediate managers were a little resistant to saying that, okay, continue it, cause that’s not why I hired you,” he says with a laugh.
Luckily, upper management saw things differently. They promoted Kessler the next year, and put him in charge of a new department dedicated to researching orbital debris.
The job of tracking debris, however, has traditionally fallen to the United States military.
“As soon as the space age began, you wanted to know where the satellites were. And we already had a system in place for warning us when missiles were coming at the United States,” says McDowell.
This was at the height of the Cold War; Sputnik and the ‘Space Race’ had the Air Force on high alert.
“And so the same radar systems and computer systems that were built to warn us of missile attacks were adapted to keep track of all the space junk, initially just so we could know its not a missile,” he says.
The command center for this tracking system was in Colorado, burrowed into the side of Cheyenne Mountain.
Today, the Air Force still tracks space debris, but in a less secretive fashion. It makes publicly available some of the orbital data for about 22,000 tracked items.
So, there’s lots of eyes on it. Now, the question is, what exactly to do about all that junk?
“I think there’s been a lot of discussion about, for example, using lasers from the Earth to zap pieces of small debris and melt them; using butterfly nets made of aerogel to snag up pieces of space debris. And I don’t think those are super practical ideas,” says McDowell with a chuckle.
A more likely solution, according to McDowell, is to go after just the larger pieces, including the old satellites, possibly pushing them out into unused orbits or safely bringing them down.
But there isn’t consensus on how to do this, or who should do it, or who should pay for it.
Brian Weeden with the group Secure World Foundation, which advocates for the long-term use of space, says the challenge of getting everyone on board is a good example of a well-known economic theory: the Tragedy of the Commons.
“Put simply, the notion is that if you have an area that is shared by everybody, that is common to everybody, and the classic example is a grazing area for a farm or a village,” says Weeden, “where everyone grazes their animals in one area but nobody owns it, you can run into a situation where it is in everyone’s own selfish interest to use it to their own advantage.”
No one is paying attention to the collective damage that overuse will cause.
“Translate that to space, this is a big question everyone has. Space is big, but there are certain regions in orbit that are very useful, and so there is a lot of satellites, and they are used by a lot of countries,” he says.
More than 60 different countries have launched satellite, including Israel, China, Iran, and North Korea. Actors, needless to say, unaccustomed to working together.
There is no governing body, and no widely adopted rules yet for how to minimize current or future debris in space.
“So in many ways, it is sort of similar to this whole question of climate change, where we know there’s going to be a problem in the future, and how do you convince people to take some action today, to deal with what’s going to be a potentially really serious issue decades from now,” says Weeden.
He adds there’s no easy solution here. It’s everyone’s problem, and nobody’s problem at the same time.
Some countries, including the U.S., have implemented policies requiring new satellites to have an exit strategy. But our previous space sins, and the sins of others, aren’t going to be washed away any time soon.