(Illustrations: Ibrahim Reintkatath)
In 1957, the Soviet Union launched the first artificial satellite, Sputnik. Since then, the space above Earth has been flooded with thousands of satellites, and depleted rocket stages and debris from many cataclysmic events. As a result, Earth’s lower orbit is littered with an increasing amount of junk that is hurtling through space at breakneck speeds, threatening satellites and even the International Space Station.
In the past year, the problem has become serious enough to prompt the Biden administration to demand that tests that destroy satellites in orbit be cancelled. The announcement came after Russia blew up a dead satellite in 2021, creating a massive debris field that threatened astronauts on the International Space Station along with other satellites.
In the future, if the international community can’t come up with a way to regulate the Wild West of space, the debris problem will only get worse. Every year there are dozens of close collisions between active satellites or pieces of debris. The more satellites flooding Earth’s orbit, the higher the chances of this happening. The more collisions, the more debris – all fueling what many fear will become a devastating cycle.
The lower Earth’s orbit is crowded with a number of objects – including working satellites as well as space debris such as defunct satellites, spent rocket stages, and debris from missile strikes and collisions.
There are more than 6,000 active satellites orbiting Earth as of January 9, according to LeoLabs, a company that tracks satellites and debris in Earth’s lower orbit. Some are small, about the size of a shoebox; Others are much larger. Their functions vary widely, from providing television and internet service to GPS and weather monitoring.
Satellites cannot live forever. It eventually runs out of fuel, or it malfunctions and becomes giant pieces of trash flying around the Earth. Currently, there are more than 1,800 damaged satellites in low orbit. Under current rules, the United States requires satellites to deorbit — or burn up in Earth’s atmosphere — after 25 years. But many believe regulation is too lax and that satellites should be deorbited early.
Over the years, spacewalk astronauts have dropped a camera lens cap, a screwdriver, and even a spoon—adding to the bizarre collection of objects in orbit, which includes worn spacecraft parts and baseball-sized pieces of trash.
Even small pieces of debris—a nut or even a speck of paint—can cause serious space damage.
Exhausted missile stages
When rockets go into orbit, they often discard the upper stages that have their engines and propellants. If they do not burn up in the atmosphere or return to Earth, they will join the space debris cloud in low Earth orbit. Many are about the size of a school bus, spinning wildly as they move through space. In total, there are approximately 1,000 spent rocket stages of various sizes in lower Earth orbit.
The United States and private companies like LeoLabs are tracking tens of thousands of pieces of space debris, including operational and non-operational satellites, rocket stages, and unknown objects. But there are so many pieces that are too small to see. NASA estimates that there is approximately 500,000 pieces They are between 1 and 10 centimeters in diameter orbiting the Earth, and there are more than 100 million particles larger than 1 millimeter in size. (The agency said that as of January last year, the amount of material in orbit was more than 9,000 metric tons.)
And with more and more companies flooding Earth’s orbit with an increasing number of satellites, there is growing concern that collisions – which would only result in more debris – are inevitable, he hypothesized. NASA scientist Donald J. Kessler in 1978.
If nothing is done, space could become so polluted that it is unsafe for human exploration and could leave some of the world’s most sensitive satellites, which are used for global positioning (GPS) and missile warnings, in peril.
Despite the growing number of space launches and debris, there are very few rules of the road in space. While the Pentagon issues warnings about potential collisions, it cannot order the operator of a spacecraft to move out of the way.
Fortunately, there are a number of steps that governments and companies are taking to reduce the space junk problem. The Biden administration has called for a ban on all destructive anti-satellite tests and, most recently, the Pentagon fired program called Orbital Primeunder the US Space Force that will give companies seed money to develop the technology needed to clean up space.
This includes grappling large objects and pulling them out of orbit (one company working with the European Space Agency suggests using spacecraft with large arms that could act like a Venus flytrap), refueling or repairing them so they last longer and maneuvering in space.
To track orbital debris, the Pentagon and commercial companies rely on a network of ground-based radar and optical telescopes. Radars can measure the distance to their targets and some can track more than one object at a time, according to the Secure World Foundation, a research organization. Telescopes collect light reflected from debris and can cover large areas quickly and at high altitudes. The US Space Force says it is tracking more than 40,000 objects in space the size of a fist or larger. But there are at least 10 times as many smaller objects in orbit that the Pentagon cannot reliably track.
In the end, many space officials say that cleaning up space will require foreign governments to work together.