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NASA’s TIMED satellite narrowly avoided a collision with the dead Russian spacecraft Cosmos 2221 this week.
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At its worst, the collision would have thrown 7,500 pieces of debris into low Earth orbit.
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Satellite collisions are becoming increasingly likely as the amount of space junk in low Earth orbit grows.
Two satellites nearly collided in space Wednesday in a harrowing encounter that LeoLabs, a satellite tracking company, called “too close for comfort.”
NASA’s Thermosphere Ionosphere Mesosphere Energetics and Dynamics (TIMED) satellite passed the defunct Russian spacecraft Cosmos 2221 at a distance of less than 20 meters. That is shorter than the length of a tennis court.
Both satellites are non-maneuverable, meaning neither the US nor Russia have control over where they go.
Had they collided, both satellites could have been decimated, blasting 2,500 to 7,500 fragments of space debris into Earth’s orbit, which would now be hurtling around our planet at thousands of miles per hour, faster than bullets.
The fragments would not have posed a threat to life on Earth, as any fragments that entered our atmosphere would have burned up during free fall.
But it would have threatened future space flights and astronaut lives, as the resulting debris could have made navigating low Earth orbit much more treacherous.
“There are ‘bad neighborhoods’ where these massive desolations preferentially accumulate,” LeoLabs’ Senior Technical Fellow Darren McKnight told Business Insider in an email.
Avoiding collisions in these crowded areas becomes increasingly difficult as the number of objects in Earth’s orbit grows every year.
Earth’s orbit is becoming overcrowded
Near-collisions between large space objects like these are rare, but it only takes one to completely change the landscape of Earth’s orbit and endanger countless other satellites, space telescopes and even the International Space Station.
For example, two satellite collisions that occurred in 2007 and 2009 respectively increased the amount of large debris in low Earth orbit by about 70%.
And with the advent of mega-constellations of internet satellites, such as SpaceX’s Starlink and Amazon’s Kuiper, the number of objects in low Earth orbit is growing more and more every year, increasing the risk of collisions.
In 2007, scientists estimated about 10,000 low-Earth objects. By 2021, that number had doubled. And most of it isn’t even useful: it’s space junk.
According to LeoLabs, about 70% is debris from damaged or defunct rockets, satellites and non-operational payloads.
However, that is exactly what has been catalogued.
The European Space Agency estimates that almost 1 million pieces of debris between 1 cm and 10 cm orbit the Earth, while another 130 million pieces are even smaller.
Space junk is so ubiquitous that the International Space Station sometimes has to navigate around it.
In March 2023, the ISS avoided objects twice a month: once to avoid a collision with a satellite and again a few days later to maneuver around debris.
Even the smallest debris can damage the space station and endanger astronauts, although no astronaut has lost their life to space debris (yet).
The race to clear space
The consequences of space debris are so real that the worst-case scenario has a name: the Kessler syndrome.
In this scenario, a collision sets off a chain reaction, creating a catastrophic domino effect that produces so much space debris that no spacecraft can safely leave Earth for hundreds or even thousands of years.
However, preventing collisions today can offset a possible Kessler syndrome scenario in the future. And some governments and private companies have begun to address the problem.
New standards in the space industry and even policies in some countries are pushing satellite operators to design their spacecraft to self-destruct when it dies, pushing themselves into a free fall that causes them to burn up in the atmosphere.
Last year, the Federal Communications Commission—the U.S. agency that regulates most communications satellites—took its first-ever enforcement action related to space debris when it fined Dish Network $150,000 for improperly disposing of a scrap satellite.
Some governments seem less concerned. Both India and Russia tested anti-satellite missiles by destroying their own satellites in orbit, creating new clouds of debris.
As for old, inoperable spacecraft wandering loose in orbit, like Cosmos 2221, NASA outsources research and development to private companies to collect them.
In September 2023, the space agency awarded TransAstra $850,000 for their concept of “Flytrap” space debris collection bags – essentially giant high-tech garbage bags that would scoop up a lot of space debris.
Outside the US, other companies are coming up with their own innovative disposal solutions. The Japanese company Astroscale designed a spacecraft with a magnetic plate that can attach to dead satellites and pull them into free fall.
But these space-clearing technologies are still being tested. The European Space Agency plans to be the first to remove a piece of debris from Earth’s orbit with its Clearspace-1 mission, set to launch in 2026.
Meanwhile, LeoLabs hopes its precision data on objects in orbit will help satellite operators predict and avoid near-collisions like Wednesday’s.
Read the original article on Business Insider