Space junk is time bombs swimming in space

The launch of the first Soviet satellite "Sputnik-1" in 1957 marked the beginning of a new era of space conquest, after which man was able to send thousands of them in the field of communications, earth observation, navigation and scientific research, and to dozens of spacecraft, robotic explorers and astronomical observatories to explore planets, asteroids and other celestial bodies, probe the depths of the universe, and build floating space stations in space inhabited by humans.

These discoveries have advanced our understanding of the universe, conducted in-depth studies in space to improve our lives on Earth, and thousands of satellites orbiting the Earth have contributed to a huge leap in communication technologies, accelerating digital transformation and improving remote sensing technologies to avoid environmental and climatic disasters facing our planet.

However, similar to the pollutants and waste left by human activities from the deepest point of the oceans to the highest level of the planet's atmosphere, thousands of debris have been sent into space by human activity outside the atmosphere and pose a potential danger if it falls to Earth or collides with other artificial objects in space.

In a first such move since the conquest of space began more than six decades ago, the US Federal Communications Commission recently fined Dish Network $6,150 for leaving debris in outer space.

The FCC investigation found that the company had violated the Communications Act and licensing conditions to dispose of the Eco Star-7 satellite after its mission ended, in orbit well below the altitude required by its licensing terms, which could raise concerns about orbital debris at such a low altitude.

What is space junk and how does it arise?

Space junk or orbital debris is the "waste" that orbits the planet and that humans leave in space.

These space debris can be disabled or abandoned satellites after the end of their mission, or the result of the explosion of objects sent into space, such as the remnants of the upper stages of rockets that carry spacecraft and satellites into outer orbit, and some space debris can result from the collision of satellites with each other, or the separation of some parts of spacecraft during takeoff or landing.

Several countries, including the United States, China and India, are testing the use of rockets to practice blowing up their satellites, generating thousands of new pieces of dangerous space debris.

Some space junk from manned vehicles and robots explored have also been left on the moon.

Most scientific satellites dedicated to Earth observation in low Earth orbit at an altitude of about 160 to 14,<> kilometers, and in comparison, most commercial aircraft fly at altitudes of only about <> kilometers, so this field at its lowest level is far enough from the Earth's surface to avoid the drag forces caused by gravity.

But some objects in low Earth orbit can return quickly, if they enter the Earth's atmosphere again, and they often burn in the atmosphere before they reach the Earth, and if some parts remain unburned, they often fall into the seas and oceans that make up more than 70% of the blue planet's surface, or in uninhabited areas that make up most of the land area.

As for satellites dedicated to communications and weather monitoring, they usually fly in high Earth orbit, at altitudes of up to 36,<> kilometers, and this field is called synchronous geographical orbit, where satellites remain stationary relative to the Earth as they rotate in the same direction of their movement, and their orbital cycle takes the same amount of time required for the Earth to rotate around itself, and space debris or satellites left at such altitudes can continue to orbit the Earth for hundreds or even thousands of years.

According to figures from the United Nations Office for Outer Space Affairs, there were 11,330 individual satellites orbiting the Earth at the end of June 2023, an increase of 37.94% since January 2022 when last year saw the largest number of objects launched into space in a single year, with 2474,<> objects leaving the planet.

The first half of 2023 has already seen 1354,<> objects launched into space, and with the development of satellite technologies and the low cost of building and launching them, this number is expected to increase significantly in the coming months.

Potential risks

Fortunately, in the history of space conquest, no human has been infected with debris from space objects: of the 29% of the planet's land area, forests occupy 32%, deserts occupy another 30%, and the rest is distributed between plains, mountains, agricultural lands, dry and arid lands, most of which are uninhabited, although the danger remains.

In May 2020, the 18-ton base stage of China's Long March 5B rocket returned to the atmosphere from orbit in an uncontrolled manner after it was used to launch an unmanned experimental capsule, and debris from the rocket's body, including a 12-meter-long tube, fell on two villages in Ivory Coast, damaging several buildings.

Just a year later, another 18-ton base stage of rockets of the same model as the previous one reached, uncontrollably, low-Earth orbit, after being used to launch part of China's new space station. But this time it crashed in the Indian Ocean, and these two rocket stages were among the heaviest objects to enter again in an uncontrolled manner since the Soviet Union's Salyut-7 space station crashed in 1991 in uninhabited areas of the South Pacific.

But the greatest danger is from satellites placed in orbit by man, as the impact of these objects with space debris leads to their destruction and loss of contact, and thus countries incur significant material and scientific losses.

For example, in March 1, the Chinese Yunhai 02-2021 satellite collided with a piece of space debris 10-50 centimeters wide that turned out to be part of the Russian Zenit-2 rocket that launched the Tselina-2 spy satellite in September 1996, preceded by a collision in February 2009 that destroyed an Iridium Satellite satellite due to a consumer and out-of-service Russian satellite.

Although they are relatively rare accidents compared to the large number of active and consumed satellites in orbit, as the number of space objects orbiting the Earth increases dramatically, many of them are more likely to spiral out of control, thus forming additional tons of space junk that may hit manned stations placed by humans in low orbits, such as the International Space Station, which orbits at an altitude of about 400 kilometers above the Earth's surface.

The space station was already exposed in May 2021 to orbital debris that hit a robotic arm outside the station and caused a hole in the boom and thermal cover without disabling it, and the station annually takes maneuvering measures to avoid collision with space debris, and one of these maneuvers occurred in November 2021, when the ISS boosted its altitude to avoid debris from testing a Russian anti-satellite missile.

Debris travels in space at a speed of about 10 kilometers per second, equivalent to 300 times the maximum speed set for cars on highways, posing a great danger not only with large-scale debris, but even small waste such as a paint slick can pose a serious risk if it breaks off from a spacecraft.