Where are artificial satellites lost?

 Where are artificial satellites lost?

Communications satellite orbiting Earth(Getty)

In 1957, on October 4th, the artificial satellite Sputnik-1 was launched into space, marking the beginning of mankind's journey into space by the Soviet Union. After 21 days, when the battery ran out, communication with the satellite was lost, and it became detached from Earth. This machine, weighing 86.6 kilograms or 184 pounds, created by humans, had orbited the Earth a total of 1,440 times, symbolizing the era of artificial satellites. Exactly four months later, on January 4th, it reentered the Earth's atmosphere and disintegrated in space.

That was about 66 years ago. Since then, science and technology have advanced significantly. As of May 4th of this year, the International Astronomical Union has listed approximately 7,702 active artificial satellites from 40 countries around the world. Most of them are in low Earth orbit, which means they orbit the Earth at an altitude between 200 and 2,000 kilometers or 124 to 1,200 miles. Typically, an artificial satellite remains active for about 15 years. After that, it becomes space debris or a non-functional satellite. Now the question arises, what happens to expired non-functional satellites?

Like Sputnik-1, certain components of some satellites in low Earth orbit, as they reenter the Earth's atmosphere on their way back, get heated due to contact with the atmosphere and burn up. Some remain partially intact, while others disintegrate and continue to revolve around the Earth. The number of such revolving objects has surpassed millions long ago. They rotate around the Earth at a speed of approximately 28,000 kilometers or 17,400 miles per hour, which is about 23 times faster than the speed of sound. Due to such high velocity, each disintegrated object poses a significant risk in terms of collisions.

From an altitude of 36,000 kilometers or 22,000 miles above the Earth's surface, the geostationary orbit, non-functional satellites known as geostationary graveyard satellites are sent approximately 300 kilometers or 186 miles away. This region of the orbit is referred to as the "graveyard" or "cemetery" of non-functional artificial satellites.

In this regard, the European Space Agency has signed a contract worth 110 million euros with a Swiss startup called ClearSpace to bring back a 112-kilogram or 247-pound non-functional satellite named Vespa, which is currently orbiting in the lower Earth orbit, back to Earth in 2026. This complex mission of removing stationary artificial satellites in deep space will be the first of its kind.