‘China is not following the rules’ as scientists warn of the risk of space debris

THE European Space Agency had to wait anxiously this week for an old satellite to descend back to Earth.

What remained of the ERS-2 satellite eventually crashed into the Pacific Ocean, an event that will become increasingly common as the number of satellites sent into space becomes more common.

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Space debris expert Professor John L. Crassidis spoke to The US Sun about the dangers associated with debris and whether falling space junk is an increasing threat.

Crassidis says whether space debris will become a common problem for us on Earth will depend on several factors.

“It really depends on a number of factors. Size is the biggest factor,” he told us.

“Most of the stuff that comes down is controlled to disappear into an uninhabited area in the Pacific Ocean.

“Typically, any satellite and debris that is in low Earth orbit burns up in the atmosphere.

‘We should not build satellites from hard materials, such as titanium, because it does not burn like aluminum.

“As the number of satellites increases, more will certainly come down, but most of them will burn up in the atmosphere. However, some countries do not follow our rules.

“For example, some Chinese rocket bodies came back to Earth uncontrollably. This can be avoided.”

As Crassidis notes, the remains of a Chinese rocket booster fell back to Earth uncontrollably in late 2022.

This caused much controversy and concern, as it was unclear where the debris would fall and what damage it might cause.

“Once again, the People’s Republic of China is taking unnecessary risks with the uncontrolled return of their Long March 5B rocket stage. They did not share specific trajectory information needed to predict landing zones and reduce risk,” NASA Administrator Bill Nelson said at the time.

“It is critical that all spacefaring nations be responsible and transparent in their space activities and follow established best practices, especially for the uncontrolled return of large rocket debris – debris that could very well cause major damage or loss of life.” Nelson warned in a statement.

The chance of a human being struck by a falling piece of space debris is still estimated at less than one in 100 billion per year.

Crassidis says we shouldn’t worry that the risk will increase in the coming decades.

“No human has ever been injured by space debris falling from the sky. Obviously, getting struck by lightning is a much higher probability, so no one has to worry about space debris right now.

‘We are putting many more satellites into low Earth orbit.

“This will obviously increase the likelihood, but it will take decades before it reaches a point where we need to worry.”

The expert called Kessler syndrome a bigger problem.

Kessler syndrome is a concept coined by NASA scientist Donald J. Kessler.

It refers to the idea that a chain reaction of exploding space debris could create so much space junk in low Earth orbit that we would be stuck on Earth.

This could also mean that people cannot use satellites because they disintegrate in collisions.

“The biggest problem is space debris hitting satellites. In 2009, two large satellites collided,” Crassidis told us.

“That sent us a HUGE message that we’re not even tracking the big things as closely as we think.

‘Everything in space moves very quickly at a speed of 27,000 kilometers per hour. They have to go that fast to get into orbit, otherwise Earth’s gravity will pull them back.

“This goes right back to Newton. When you see an astronaut ‘floating’ in space, you shouldn’t think of him or her that way.

“They actually fall at a speed of 27,500 km per hour, but never hit the ground. The problem we are concerned about is that space junk collides with other space junk or satellites, creating more space junk, leading to a cascade effect.

“This is known as Kessler syndrome. Clearly this will be bad if it becomes a reality.”