The race to clean up space junk

Startups and governments are experimenting with everything from robotic arms to navigation satellites that fall out of orbit amid the growing amount of space junk.

When a satellite expires and is no longer usable, it will continue its orbit. A booster after completing the mission of putting the spacecraft into orbit will also be left in the air. And when two objects in space collide with each other and create millions of fragments, they are also left behind in space.

Moving uncontrollably at high speeds, such debris can collide with multibillion-dollar constellations owned by companies such as SpaceX or crash into strategic assets of the United States, China and many other governments.

Unfathomable danger

As big as a truck or as small as a coin, space junk is a threat to the global space industry. They fly in orbit at 8 kilometers per second, 10 times faster than the speed of a projectile, according to CNN. At the above velocity, a fragment as small as 1 cm on impact will have the same explosive power as a grenade.

The first objects that could be affected by space debris are satellites or spacecraft flying close to Earth, such as the International Space Station (ISS).

With an average orbital altitude of about 330 kilometers, the ISS is located right at an altitude with many pieces of space junk. The large size of the ISS also makes it more likely that it will be hit by debris.

Space junk that exists around the Earth is at an alarming level. Photo: BBC.

The second female astronaut in Japanese history, Naoko Yamazaki, witnessed firsthand the dangers of space junk when she flew to the ISS in 2010.

“During the flight we saw a small scratch in the window of the ship,” she told CNN. “We took pictures on the ground to check if the flight back to Earth was safe.”

Scratches smaller than 1 inch (2.45 cm) are not dangerous. If her ship were to hit a larger piece of space junk, it would be a disaster.

According to the Guardian, the ISS has to move every year to avoid collisions with space junk that have the potential to destroy the station. However, according to CNN, the ISS can only avoid objects that can be monitored from Earth.

According to a report in September 2023, the US Federal Aviation Administration (FAA) expects that by 2035, there will be 28,000 dangerous debris from satellites in low Earth orbit that can return to the atmosphere, causing injury or death to a person on the ground every two years.

However, less than a year after that report, the cylindrical object that fell from the top, tore off the roof and pierced through two floors at a house in Naples, Florida, on March 8 was taken to the Kennedy Space Center in Cape Canaveral for analysis, the Washington Post reported.

Based on the results, the US agency determined that this was a metal bracket used to attach the battery, coming from NASA’s flight support equipment. The metal block weighs 0.7 kg, is 10 cm high and about 4 cm wide.

Debris from the ISS fell into a house in Florida, USA. Photo: Otero.

The U.S. agency said the container had been removed from the space station since 2021 and should have been destroyed in the atmosphere, it did not know why the debris appeared and was committed to investigating the cause of the incident.

This is not the first time space junk has fallen to the ground. In 2021 and 2022, debris from SpaceX rockets fell on a farm in Washington state and another in Australia. Skylab, the first U.S. space station, also crashed into Western Australia.

Competing to clean up garbage

The problem of space junk becomes even more urgent as the number of satellites launched increases. The dense existence of space junk also makes it increasingly difficult to launch rockets.

When launched, the rocket’s speed is fast enough not to collide with pieces of space junk floating in the air. However, the more later, the more space junk will be, making it more difficult and expensive to launch rockets.

Over the years, there have been a series of startups quietly researching methods of tracking, capturing or treating space junk with technology such as robotic arms, inflatable bags and high-power lasers.

The Nimbus satellite, which is expected to fly 450 kilometers from the planet by the end of 2024, will only have a lifespan of a few months. It could then join a collection of man-made objects that remain in orbit for years, or sometimes decades after their expiration date.

Taking advantage of small amounts of particles from the upper atmosphere, Solstorm’s parachute-like device will slow down the satellite, enough for it to fall out of space and burn harmlessly within a year, 16 times faster than normal. Photo: Bloomberg.

However, the Norwegian company Solstorm has other plans to have the tiny Nimbus satellite move itself out of its way by deploying a tugboat to slow it down, allowing it to fall into the Earth’s atmosphere and burn without harm for a year.

NASA, the European Space Agency (ESA) and several other startups have tested such sails. Solstorm is now one of many companies that are expected to be able to apply them to satellite suicide trips.

“We will show the world how easy it is to carry out sustainable missions. This is completely possible, without the need for super-complex rocket engines,” said Halvor Veiby, CEO of Solstorm

Founded in 2013, Astroscale (Japan) has raised more than $380 million and plans to list its shares on the Tokyo Stock Exchange’s growth market.

In 2021, the company was honored to successfully launch the world’s first space garbage removal satellite. Called ELSA-d, the satellite uses a magnetic system to collect a simulated piece of debris in orbit.

Astroscale plans to collect space junk using a robotic arm equipped on a satellite and burn it in the atmosphere. Photo: Bloomberg.

The success of ELSA-d has become the impetus for Astroscale to plan to collect space junk using a robotic arm equipped on a satellite and burn it in the atmosphere.

Besides the huge cost, there is also a painful problem for space junk startups to be able to operate is ownership.

Under international law, space debris remains the property of anyone left behind, even after decades.

This means that companies need to be licensed before attempting to carry out debris removal tasks. Russia and China are the two countries that hold the majority of space junk sovereignty, and with the current geopolitical tensions, getting approval is not easy.