Executive summary
Space threatens us in more ways than Hollywood blockbusters suggest. Beyond the dramatic asteroid impact scenarios, we face solar flares that could cripple power grids, space debris that endangers satellites, and cosmic events that could disrupt the technology-dependent civilisation we’ve built. Yet humanity is responding with remarkable ingenuity, developing technologies that could fundamentally change our ability to defend against cosmic threats.
- Socio-economic losses from severe space weather events could reach US$1-2tr annually, according to the US National Academy of Sciences.
- Advanced space weather forecasting systems now provide hours of warning before solar storms hit Earth’s infrastructure.
- AI-driven surveillance networks track over 35,000 objects in orbit, predicting collision risks with near-perfect accuracy.
- Kinetic impactor technology has proven capable of altering asteroid trajectories, as demonstrated by NASA’s DART mission.
- Nuclear deflection simulations show promise for redirecting large asteroids that pose existential threats.
These technologies essentially mean that we’ve gone from crossing our fingers to actively managing cosmic risks with the same methodical approach we apply to weather forecasting or air traffic control. The infrastructure of planetary defence is quietly assembling itself above our heads, transforming existential dread into an engineering problem with increasingly sophisticated solutions.
Have you ever looked up at the night sky and wondered whether we’re truly alone in the universe? And if intelligent life does exist beyond our pale blue dot, would these cosmic neighbours arrive with peaceful intentions or harbour more sinister plans for humanity? While scientists continue searching for definitive answers about extraterrestrial life, one thing remains crystal clear: outer space presents very real dangers that could threaten our civilisation or even obliterate Earth entirely. Whether it’s solar flares capable of crippling our electrical grids, chunks of space debris hurtling toward our planet at devastating speeds, or massive asteroids following collision courses with our world, the cosmos certainly offers no shortage of horrifying potential disasters.
Recognising the magnitude of these threats, researchers across the globe have dedicated themselves to developing sophisticated technologies that would not only offer early warning systems for incoming dangers, but also provide us with defensive capabilities to neutralise them before they can cause harm. From advanced telescopic arrays that scan the heavens for approaching objects to experimental deflection systems designed to alter asteroid trajectories, the scientific community has marshalled impressive innovation in humanity’s defence. Let’s examine some of the most compelling examples of these protective technologies and explore how they might safeguard our future against the perils lurking in the vast darkness above.
Space weather forecasting
Without the Sun, there would be no life on Earth. And yet, it can also cause some serious harm
Our Sun sustains all life on Earth, providing the energy that drives photosynthesis, weather patterns, and the fundamental processes that make our planet habitable. But this same cosmic furnace that enables our existence also generates space weather phenomena that could bring our technology-dependent civilisation to an absolute standstill. Solar flares – explosive eruptions on the Sun’s surface – can unleash electromagnetic radiation and charged particles that wreak havoc on our satellite networks, disrupting everything from GPS navigation to financial transactions. Astronauts also face heightened radiation exposure during these events, potentially limiting mission durations and threatening crew safety. The US National Academy of Sciences estimates that severe space weather events could generate socio-economic losses of US$1-2tr annually in worst-case scenarios.
Accurate space weather prediction could significantly reduce these risks, but achieving this is no small feat. The intricate mechanisms driving solar activity, combined with relatively sparse observational data, make it extraordinarily difficult to make accurate predictions. Traditional prediction methods have depended heavily on human expertise and accumulated knowledge, an approach that often fails when faced with sudden, unpredictable solar eruptions. Recognising these limitations, the Japan Aerospace Exploration Agency (JAXA) joined forces with tech giant Fujitsu and the Tokai National Higher Education and Research System to develop what they describe as the world’s first model for pinpoint solar flare prediction.
The system uses AI to analyse satellite data collected by JAXA and other space agencies, which is then fed into Fujitsu’s supercomputer to run numerical simulations that calculate the probability of solar explosions and model how they propagate through space. “Similar to earthquakes, large solar flares are extremely rare,” explains Dr. Kanya Kusano, Professor Emeritus at Nagoya University. “Fujitsu Kozuchi XAI quickly identifies important parameter combinations from limited data. We then integrate our physical knowledge to generate new, physics-based predictions and create new parameters. These parameters are then re-evaluated using AI, creating a synergistic effect.”
Tracking space debris
Near-Earth orbit is full of space debris hurtling through space at tremendous speeds, posing a threat to our satellite networks. How do we track it?
Of course, solar flares represent just one category of cosmic hazards threatening our increasingly connected world. Space debris presents equally serious risks, with space junk accumulating in Earth’s orbit at an alarming rate, fueled by the growth of the space industry. Space debris consists primarily of defunct satellites, spent rocket stages, and countless fragments created through disintegration and collision events. These objects hurtle through space at approximately 27,350 kilometres per hour on average, fast enough to transform even small pieces into devastating projectiles. The International Space Station regularly adjusts its orbit to avoid potentially catastrophic encounters, while operational satellites that underpin our communications, navigation, and weather monitoring systems face constant collision risks.
A US startup called Privateer has developed an AI-driven solution to address this growing menace. Their platform, Wayfinder, combines data from multiple sources, including the US Space Command and various satellite operators, to create a comprehensive tracking system that can alert satellite operators before dangerous encounters occur. The system currently monitors more than 35,000 objects in orbit, although this figure only includes debris larger than 10 centimetres.
Objects below this threshold are too small to be observed from Earth, and the company estimates that approximately 100 million pieces of space debris larger than 1 millimetre currently orbit our planet. “To be able to track that many objects and be able to plan to predict where their orbits will be over the next 24, 48, and 72 hours requires a lot of data and a lot of computational power, and we’re able to leverage the power of AI to do that in a fraction of the time that it previously took humans to do,” says Declan Lynch, Privateer’s Chief Revenue Officer.
Asteroid hunter
Asteroid impacts are rare, but they do occasionally happen. Scientists want to make sure they never catch us off guard.
Some objects lurking in the cosmic neighbourhood dwarf those 10-centimetre fragments by many orders of magnitude. In fact, Earth receives a constant barrage of tiny space rocks every single day, with most burning up harmlessly as meteors in our protective atmosphere. However, larger visitors occasionally survive the journey down, and when they do, the consequences can be catastrophic. The asteroid that exploded over Chelyabinsk, Russia, in 2013 shattered windows across the city and injured over 1,000 people with flying glass, while the much larger impact 66 million years ago ended the reign of the dinosaurs and reshaped life on our planet. Between these extremes lies a spectrum of potentially dangerous asteroids that could cause significant regional or global damage if they found their way down to Earth.
NASA’s Near-Earth Object (NEO) Surveyor mission plans to address this threat through systematic detection and tracking. Scheduled for launch in September 2027, NEO Surveyor is designed to find and study near-Earth objects that might pose collision risks. It’s essentially a 6-metre-long, infrared telescope that will be positioned at a gravitational sweet spot approximately 1.5 million kilometres from Earth. At this location – known as the L1 Lagrange point – the gravitational forces from the Sun and Earth balance perfectly, allowing spacecraft to maintain stable, efficient orbits with minimal fuel consumption. From this vantage point, NEO Surveyor will be able to scan both ahead of and behind Earth’s orbital path, enabling it to detect asteroids that would otherwise remain invisible from our planet due to solar glare.
Ground-based asteroid surveys face numerous limitations that NEO Surveyor will circumvent. Weather disruptions can halt observations for days or weeks, while atmospheric interference makes it difficult to spot smaller bodies near the Sun. Many ground-based telescopes also provide limited coverage of the Southern Hemisphere, creating blind spots in our planetary defence network. Operating in the infrared spectrum gives NEO Surveyor a crucial advantage in detecting asteroids that would otherwise remain hidden. “Even asteroids as dark as a chunk of coal won’t be able to hide from our infrared eyes,” explains Amy Mainzer, principal investigator for NEO Surveyor at the University of Arizona. “With NEO Surveyor, we want to spot potentially hazardous NEOs when they’re years to decades away from possible impact. The whole idea is to provide as much time as possible to develop mitigation efforts that enable us to push them out of the way.”
“Choosing to employ a nuclear device is a serious and potentially grave decision.”
Patrick King, a physicist at Johns Hopkins University
How to divert an asteroid
What’s the best way to push a massive body of rock off course?
However, detecting an asteroid on a collision course with Earth is just the first step; we also need reliable methods to destroy these threats or nudge them away from our planet before impact. NASA’s Double Asteroid Redirection Test (DART) was the first space mission designed to test our planetary defence capabilities using the kinetic impactor technique, which essentially involves ramming spacecraft into asteroids at high velocity to alter their trajectories. In September 2022, the DART spacecraft reached the near-Earth asteroid Didymos and deliberately crashed into Dimorphos, the asteroid’s small moon. The collision successfully changed Dimorphos’s orbital period around Didymos by 33 minutes, demonstrating that kinetic impactors can effectively modify asteroid orbits. However, this technique has clear limitations; it only works with asteroids small enough to be meaningfully influenced by spacecraft impacts.
As a result, many scientists have turned their attention to a more controversial alternative that could handle massive asteroids appearing suddenly on collision trajectories: nuclear weapons. Physicists at Sandia National Laboratories recently conducted experiments showing how an intense radiation pulse from a nuclear explosion could vaporise sections of a nearby asteroid. The process generates surface temperatures reaching tens of thousands of degrees, creating a rapidly expanding gas ball capable of pushing the asteroid off its original path. “The vaporised material shoots off one side, pushing the asteroid in the opposite direction,” explains Dr. Nathan Moore, the study’s first author. “It’s like turning the asteroid into its own rocket.” Understandably, this approach has generated some concern within the scientific community. “Choosing to employ a nuclear device is a serious and potentially grave decision,” warns Patrick King, a physicist at Johns Hopkins University.
Learnings
The technologies emerging to shield us from cosmic threats reveal something profound about humanity’s evolving relationship with the universe. We’ve moved beyond simply gazing up at the stars in wonder or fear – we’re actively preparing to defend ourselves against the very cosmos that created us. Each breakthrough in space weather prediction, debris tracking, and asteroid deflection carries implications that extend far beyond planetary defence. The AI systems learning to predict solar flares could revolutionise how we understand chaotic natural phenomena here on Earth. The computational power required to track millions of orbiting fragments is pushing the boundaries of data processing in ways that benefit countless other fields.
These protective technologies also hint at humanity’s expanding capabilities. Today we’re developing systems to deflect asteroids and predict space weather. Tomorrow, these same innovations might help us establish permanent settlements beyond Earth, mine asteroids for resources, or explore distant solar systems. The tools we’re building for defence could become the foundation for expansion. The universe will always be dangerous, unpredictable, and vast beyond comprehension. Yet we’re no longer helpless observers waiting to see what cosmic lottery ticket gets drawn. We’re becoming active participants in our own survival story, armed with increasingly sophisticated tools and growing confidence in our ability to adapt and overcome.
