Millions of us have seen the epic blockbuster film Gravity, starring Sandra Bullock and George Clooney, as they’re left stranded in space after things go awfully wrong on a mission to the Hubble Space Telescope.
Well, the entire concept of how things go Pete Tong is a dramatic take on something that is thought to be a very real possibility in real life.
The film follows Bullock and Clooney repairing Hubble when they get a warning from Mission Control in Houston that they need to speed things up, with a spot down spy satellite creating a debris field orbiting the Earth and heading right for them.
A domino effect follows, with the debris knocking out communication satellites as well as tearing apart Hubble and later, the International Space Station (ISS). Enter the realm of the Kessler syndrome, which scientists believe to be a very real risk as the space race hots up once again through the likes of Elon Musk and his SpaceX company.
What is the Kessler syndrome?
Humanity has been exploring space for more than half a century, with it one of the great unknowns that we can’t resist but try and learn more about.
But it isn’t without problem, with NASA scientists Donald Kessler and Burton Cour-Palais coming up with a potentially troublesome scenario.
Back in 1978, the two experts theorised that if humanity keeps on sending more and more spacecraft in to the cosmic void, we’re going to get in to trouble as it gets more and more crowded around Earth as the chances of a collision are upped.
“Spent rockets, satellites and other space trash have accumulated in orbit increasing the likelihood of collision with other debris,” NASA explains.
“Unfortunately, collisions create more debris creating a runaway chain reaction of collisions and more debris known as the Kessler Syndrome after the man who first proposed the issue, Donald Kessler.”
The Kessler syndrome brought to life in Gravity (Warner Bros.)
Why scientists are worried the Kessler syndrome will be proved true
Some experts are convinced it is just a matter of time until the Kessler syndrome is proven true.
John L Crassidis, a professor of innovation and space debris expert at the University at Buffalo, New York, said: “The Kessler syndrome is going to come true. If the probability of a collision is so great that we can’t put a satellite in space, then we’re in trouble.”
Currently, more than 10,000 satellites are orbiting the Earth. On top of that, more than 100 trillion pieces of old satellite are still circling the planet, with parts occasionally falling in to the Earth’s atmosphere over time and burning up.
Kessler demonstrated that once the amount of debris in a particular orbit reaches something called ‘critical mass’, collisions begin even if no more objects are launched into the orbit.
“Once collisional cascading begins, the risk to satellites and spacecraft increases until the orbit is no longer usable,” NASA says.
Kessler estimated that it would take 30 to 40 years to get to this point. Nowadays, some experts thing we are already at critical mass in low-Earth orbit, which is roughly 560 to 620 miles (900 to 1,000 kilometers). Events in recent years include a deactivated Russian satellite smashing into a US satellite back in 2009.
And in 2021, a Russian missile that destroyed one of its own satellites as part of a test forced astronauts on the ISS to undertake emergency procedures.
The dangers of the Kessler syndrome mean our satellites could be taken out by space junk (Getty Stock Image)
Why the Kessler syndrome could end life as we know it on Earth
If satellites and debris enter a chain reaction of collisions, life as we know it could end.
Satellites could be taken out, which could see huge internet and Wi-F outages. Phones could also go down with no satellites in the sky to ping calls from. It would even mean the potential end of TV and GPS.
And on a more general level, weather satellites could be taken out, impacting our critical ability to track its impact on a number of industries.
“Weather satellites play an important role in a variety of industries, including agriculture, fisheries, and transportation, by predicting and mitigating the effects of adverse weather conditions,” says Amrith Mariappan and John L. Crassidis in their 2023 paper entitled ‘Kessler’s syndrome: a challenge to humanity’.
They explain: “Remote sensing satellites, in turn, make significant contributions to resource exploration and monitoring of phenomena such as floods, droughts, soil moisture, wildfires, vegetation health, forest degradation, road infrastructure surveillance, etc. Remote sensing satellites are used in the military to capture high-resolution images of strategic locations, monitor enemy activities, and assess potential threats.”
The paper adds that it could devastate healthcare, with medical devices offline.
The problem in this situation, if we reach what Kessler called the ‘critical mass’ stage, is that it then becomes too dangerous to send anything in to space due to the chain reaction that is existing around the planet with debris flying at immense speed.
Life on Earth would change dramatically if the Kessler syndrome comes true (Getty Stock Image)
How to stop the Kessler syndrome
Mariappan and Crassidis write that the ‘recycling of space debris emerges as a promising and long-term sustainable solution to the mitigation of space debris’.
Another short term option being taken by some is to de-orbit waste and let it burn up in the atmosphere of Earth.
While it can remove immediate threats it is risky and poses a large environmental problem, such as the depletion of the ozone layer.
“By repurposing decommissioned satellites and debris into useful materials to support other space missions, this recycling strategy presents a win-win scenario, promoting environmental sustainability and resource efficiency in space exploration,” Mariappan and Crassidis say.
The European Space Agency says it wants to become ‘debris-neutral’ by 2030, by which it means ‘adding zero net debris to the Earth orbital environment’, with a larger aim to reuse parts by 2050.
Whether we, as a species, get to the stage where we can stop the Kessler syndrome from becoming reality remains to be seen. Efforts are under way to stop it, all we can do is hope that is enough.
Throughout his life, legendary planetary scientist Carl Sagan dedicated his work to furthering our understanding of space and the possibility of extraterrestrial life (aka aliens) existing.
Often described as ‘the scientist who made the Universe clearer to the ordinary person’, Sagan took the complex – and often mind-boggling – world of astrophysics and made it easily accessible to the likes of you and I.
In 1990, Sagan unveiled an image called the ‘Pale Blue Dot’ to the world, take a look at the image below:
The image was released in 14 February 1990 (NASA/JPL-Caltech)
Now, upon first glance I know this photo looks like an image of the night sky taken in your back garden on an old mobile phone.
However, I assure you this is not an average photo of the night sky, but instead an image captured by by NASA’s Voyager 1 around 3.7 billion miles (6 billion kilometers) from the Sun.
The subject of this photo? Planet Earth.
Look closely at the photo and you’ll notice a small pale blue dot just off centre in the upper right part of the image, that’s us.
After seeing the images, Sagan was inspired to use it as a way to drive home just how unique our situation is in the universe.
Talking about the lack of interstellar life in a press conference for the image, Sagan said: “For me, that underscores the rarity and preciousness of the Earth and the life upon it.
“On that blue dot, that’s where everyone you know. Everyone you ever heard of, and every human being who ever lived, lived out their lives.”
Urging others to use the image as inspiration to look after our collective home, he continued: “Just speaking for myself, I think this perspective underscores our responsibility to preserve and cherish that blue dot, the only home we have.”
I can think of a few people who could use such a reminder, that’s for sure.
That’s us, the blue dot (YouTube/The Planetary Society)
Like the astronauts who’ve spoken candidly about the impact of the ‘Overview Effect’, the image leave a lasting impact on Sagan. He would later go on to name his 1994 book Pale Blue Dot: A Vision of the Human Future in Space after the image.
Proving this photo is definitely not your typical image of the night sky.
The legacy of the ‘Pale Blue Dot’ has gone on to inspire more than Sagan in the subsequent years as well, with Garry Hunt telling the BBC in 2020 that he often uses the image as a way to drive home the importance of taking climate change seriously.
“Every time I give a climate talk and I talk about what you’re doing now to make a change – I show this picture because it shows the Earth is an isolated speck. This tiny blue dot is the only place we can possible live, and we’re making a jolly good mess of it,” he said in the interview.
