There is no denying humans are singularly responsible for causing so much pollution on the earth. However, from the time they started exploring space, the problem of space debris has also emerged as a major concern. Over the decades, satellites have been launched into earth’s orbit to offer GPS service, spying, and security surveillance. However, they have a lifespan, and after that, the satellites turn into space debris or junk.
A grave concern
The number of satellites in the Earth’s orbit has grown steadily, and the menace of space junk has become a grave concern. Last year, astronauts on the ISS were asked to stay inside the facility as there was a real possibility that it could be hit by flying debris. The reason was Russia had destroyed one of its satellites with a missile strike. The ISS faced many such safety risks caused by space debris.
The issue of space junk is not a new one. Initially, there were fewer satellites in space. Now, the number of satellites has grown manyfold, and some of them have become non-operational. Almost 8,000 tonnes of space waste is now encircling the world. If precautions are not taken, the debris created from defunct satellites can strike spaceships, astronauts, and other active satellites. It can lead to significant monetary loss and potentially the loss of lives.
The RAF Fylingdales, part of the U.S. Space Surveillance Network (USSN), keeps a tab on the volume of space debris. There are other risk assessment sites such as the UK Space Agency that also record many potential collision alerts.
There are currently thirty thousand pieces of deductible space junk. In addition, there are over 100,000,000 small pieces that can cause damage, too. This is because so many micrometer-sized particles are moving around the earth at a staggering speed of 15,000 mph which can strike a satellite making it unusable.
The impact on satellites can be manyfold
The menace of flying space debris can affect the satellite in many ways. They can not only be hit by the debris but also by deviating from their designated orbit; precious fuel is used, which can affect an active satellite’s lifespan. A satellite may also be forced into an orbit that is of little use to it. It can be especially detrimental to surveillance satellites.
Several countries, including Germany, China, India, and the U.S. have used missiles to destroy their defunct satellites, leading to the creation of more space junk.
There are times when clashes between satellites also can’t be avoided. For example, two defunct satellites orbiting in opposite directions can collide. When they do, that leads to the creation of more space debris. In 2009, a defunct Russian military satellite was struck by an active Iridium communications satellite. It took place over Siberia, and the clash led to the creation of thousands of fragments.
The situation may turn more challenging given that entities like SpaceX and OneWeb are now launching hundreds of small satellites into earth’s orbit. These are used to offer broadband access and other services, causing the risks to multiply.
The U.S. has declared the DA-ASAT plan to tackle the menace of space junk creation. Other space agencies are also devising newer and more effective methods to track space junk and help satellites evade clashes in orbit. There are methods that include moving satellites into a lower orbit where they will burn up on re-entry into the earth’s atmosphere. A Japanese tech firm named Astroscale plans to start a defunct satellite removal service. There is also ESA’s ClearSpace-1 mission which will go operational by 2025.
