The volume of space junk in orbit is increasing (Picture: Getty/Science Photo Libra)

‘No one gets an award for stopping a disaster that didn’t happen,’ jokes LeoLabs’ Dr Darren McKnight.

He isn’t wrong – just ask anyone who worked on the Millennium bug.

‘Everyone said Y2K wasn’t a big deal – but it wasn’t a big deal because they prevented it,’ he says.

But stopping disasters is what Dr McKnight and the team at Leolabs are all about – even if their story won’t make it into a Hollywood apocalypse film.

Leolabs is a leader in the ‘air traffic control’ of lower Earth orbit (LEO), keeping track of the near 8,000 satellites spinning above our heads at 12 kilometres a second. Perhaps unsurprisingly, these often end up on a collision course with each other – or the tens of thousands of pieces of large space debris.

Using radars across the globe, including the newly-installed Azores Space Radar boosting coverage over Europe, the company tracks satellites on behalf of commercial companies and flags any potential collisions, allowing operators to make evasive manoeuvres. 

It is no secret that the number of satellites and volume of space junk has increased rapidly in recent years, and in the last 16 months, there were 600,000 of these near-miss ‘events’. 

‘Starlink is often touted as the problem [because they launch so many satellites], but in reality they really operate the most responsibly of any constellation in Low Earth Orbit,’ says Dr McKnight.

Near misses are calculated not by distance, but the chance of them occurring. High probability is classed as one in a million. Most companies make evasive manoeuvres from a one in 100,000 chance. 

A Starlink satellite passes over Saltburn, North Yorkshire (Picture: Ian Forsyth/Getty)

‘If you imagine you’re driving on the highway – you’d slow down when you got a certain distance away from the car in front of you – but someone else might be happy to drive a metre behind you,’ he says.

‘It all depends on the individual’s risk threshold – and Starlink do collision avoidance manoeuvres at a much lower risk level than any other constellation.’

In fact, last year Starlink satellites made no fewer than 14,000 collision avoidance manoeuvres. They may have only nudged a satellite a few centimetres, but if done a day or two before a possible collision when alerted by LeoLabs, it can add up to five kilometres between two objects.

However, near misses do happen, and sometimes by as little as 50 metres.

‘That may sound like a good distance, but don’t forget the relative velocity’ says Dr McKnight. ‘They’re travelling at about 12 kilometres a second, so 50 metres is a microsecond.’

Dr Darren McKnight is tasked with helping prevent collisions in space (Picture: LeoLabs)

Dr McKnight is speaking from an empty classroom in Milan having taken a break from an international conference where orbital capacity – how much space there is around the planet – is high on the agenda.

The answer is still quite a lot, but it is getting ever more crowded, and the chance of a major collision ever greater.

When a major collision occurs – not if, says Dr McKnight – it probably still won’t be worthy of a Hollywood blockbuster. More likely it will inconvenience people trying to watch them.

‘Some things are going to get less reliable,’ he says. ‘Global communications, global connectivity like Starlink, OneWeb, Iridium may be affected.

A long exposure image of a SpaceX Falcon 9 rocket carrying Starlink satellites taking off from Cocoa Beach, Florida (Picture: Paul Hennessy/NurPhoto/Getty)

‘The problem is it’s not very dramatic, so you get an ‘oh we can wait’ attitude, but this is much like global warming – if you let things move on an exponential curve, by the time you want to control it, it’s too late.

‘Normally any major airspace catastrophe is presaged by near misses, so by us tracking these things [and avoiding crashes] people think ‘oh good, nothing’s happened’ – but the trend is not good. 

‘We’re going to have a collision.’

Key to avoiding such a calamity is the removal of ‘dead’ satellites and other space junk.

‘I believe the three governments that are responsible for the majority of the massive derelicts in low Earth orbit should act to remove them,’ says Dr McKnight. ‘Russia and China are showing no movement in this direction, but the US is starting to attack this through the ORBITS Act that is working its way through Congress. 

‘Interestingly, the European Space Agency, the Japan Aerospace Exploration Agency and the UK Space Agency are all funding efforts from technology demonstrations to actual removal even though they have not really caused much of the problem at all…’

When a big crash does occur, it will add thousands more pieces of debris to low Earth orbit, which themselves could go on to cause other crashes, and that debris could cause further crashes.

We’re not at risk of creating so much debris we can no longer leave the planet – not in our lifetime anyway – but Dr McKnight is concerned for manned space flight, which happens between the planet and most satellites.

‘Crashes happen at 600, 700, 800 kilometres, and the debris ends up working its way down through manned space altitudes,’ he says.

For example, the International Space Station orbits at a little over 400km above Earth.

The International Space Station orbits 408km above the Earth (Picture: Stephen Bowen/Nasa)

And while that’s still a long way up, every week space debris manages to survive the fiery reentry into Earth’s atmosphere and touch down. In most cases it’s more of a splashdown, given around 70% the planet is covered in water, but occasionally space hardware makes a hard landing.

‘The luck is going to run out at some point, the odds are it’s going to thump somebody,’ says Dr McKnight. ‘So far nobody has been killed, but there are speculative stories of people getting hit.’

Those include Lottie Williams, who was struck on the shoulder by what is believed to be a piece of space debris in Tulsa, Oklahoma, in 1997.

But those heading outside in Tulsa – or anywhere – need not scan the skies as they walk, because LeoLabs is already doing that for them. For those who wish to double-check, they can check out the company’s interactive map showing the satellites circling the planet right now.

The graphic is a clear visualisation of both the extraordinary number of satellites in orbit and LeoLab’s work. The latter is a happy collaboration between machine learning and the team, something those wary of an impending AI takeover can take solace in.

Last year, a piece of junk from the SpaceX Crew-1 mission landed on Mick Miners’ farm in Australia (Picture: Mick Miners/SpaceX)

‘I like to say we leverage AI and RI,’ says Dr McKinley. ‘We use machine learning in a significant number of areas, such as how to get the most out of our radars or identifying how objects are behaving.

‘But we also apply “real intelligence”, which brings subject matter expertise and context that we don’t have enough data for to train an algorithm on.

‘I love machines that tell me stuff, but I also love people who’ve done this for decades to say “don’t forget about this”.’

It seems LeoLabs won’t get a starring role in any future robot apocalypse film either – as is so often the case, the hardworking good guys stay in the background.

Yet in this scenario there isn’t a single stand out bad guy (or gal) either, simply human progression. 

But to stay on track the space industry must get to grips with the rapid growth of low Earth orbit traffic – ideally sooner rather than later.

MORE : Space has a trash problem and nobody’s quite sure how to fix it

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And the debris may hit Earth…