Category: 7. Science

The Future of AI in Space: Upcoming Missions and Breakthroughs

by Clarence Oxford

Los Angeles CA (SPX) Jul 20, 2025

What happens when artificial intelligence leaves Earth? AI now guides spacecraft, steers satellites, and helps scientists study planets billions of kilometers away. Space agencies and private companies already rely on AI to plan missions, analyze data, and make fast decisions without human help. The future of AI in space expands the way we explore and opens access to places we couldn’t reach before. In this article, we look at how AI works in space today, the missions that push it further, and the challenges that shape what comes next.

How AI powers modern space exploration

Artificial intelligence and machine learning already reshape how spacecraft operate, how rovers explore terrain, and how scientists interpret deep space data. Missions like NASA’s Perseverance Rover rely on onboard AI for autonomous navigation, choose rock samples, and make real-time decisions without waiting for instructions from Earth. This ability allows missions to continue operating during long communication gaps, especially on Mars and beyond. Space agencies and private companies turn to AI consulting services to help design autonomous systems that reduce mission workload and increase efficiency.

+ ESA’s Mars Express uses AI to avoid data loss and preserve memory, reducing mission workload by nearly 50%. According to Alessandro Donati from ESA’s Space Operations Centre, AI delivers more scientific value while consuming fewer human resources.

+ AI also filters and analyzes massive datasets generated by telescopes like James Webb and Hubble. These observatories produce terabytes of information daily – too much for human teams to process alone. AI sorts through the data, detects patterns in light curves, and helps scientists identify exoplanets and galaxy formations faster than traditional methods.

+ Beyond data analysis, AI helps to protect missions. It predicts equipment failures, optimizes satellite orientation to avoid space debris, and even handles emergency response protocols during solar flare events. NASA’s partnership with Google led to AI models that discovered previously unknown exoplanets by analyzing Kepler data – proof that AI finds what humans might overlook.

+ The SETI Institute applies AI to scan deep space radio signals for patterns that could suggest extraterrestrial life. As more missions launch, the role of AI continues to grow – not as a supporting tool, but as a core component of how humanity studies the cosmos. You can learn more about machine learning development services here.

As new challenges emerge across the solar system and beyond, the success of future exploration will depend on how well these intelligent systems perform. What once required dozens of specialists on Earth now happens in orbit, guided by machines that learn, adapt, and act faster than ever before.

Missions and future of space technology

Space agencies and private companies are investing billions in AI in space exploration, which aims to change what’s possible in space exploration. These projects mark a shift from remote-controlled spacecraft to autonomous systems that analyze, decide, and act without waiting for human commands. Behind many of these systems is a carefully trained machine learning model in Python, built to interpret sensor data, recognize patterns, and make decisions in real time. The next wave of missions will test how far AI can go on its own.

1. AI-driven missions from ESA

Space agencies are deploying AI to tackle complex, autonomous objectives. One example is ESA and JAXA’s Martian Moons eXploration (MMX) mission, which uses onboard intelligence to land on Phobos, collect samples, and return them to Earth. The mission relies on AI to navigate, select landing zones, and adapt to the moon’s unpredictable environment without continuous guidance. Similar autonomy features appear in upcoming lunar and Martian projects, where AI manages navigation, hazard avoidance, and data prioritization during surface operations..

2. Private sector innovation

Private companies are moving just as fast. SpaceX continues to improve AI systems in Starlink satellites, which already use onboard intelligence for collision avoidance and beam steering. The upcoming Starship missions may rely on similar technologies to manage landings and orbital adjustments. Blue Origin’s lunar lander also includes future space technology like autonomous landing capabilities that reduce the need for Earth-based pilots.

3. Artemis lunar base robotics

NASA’s Artemis program will deploy autonomous construction robots to the Moon starting in 2028. These AI-powered systems will build landing pads, habitats, and other infrastructure using lunar regolith. The program aims to establish a long-term human and robotic presence on the Moon, powered by real-time decision-making and collaborative autonomy. AI will manage tasks like terrain assessment, material selection, and load balancing without waiting for commands from Earth. These robots will work in teams, using machine vision and swarm coordination to adapt their roles as the mission evolves.

4. Europa Clipper

Although launching in 2024, Europa Clipper will begin AI-guided operations once it reaches Jupiter’s moon. The spacecraft will use onboard intelligence to process radar and spectral data, deciding in real time which information to keep. This use of advanced computing represents an important trend: shifting data analysis from Earth to the spacecraft itself. AI helps prioritize scientifically valuable data, conserving limited bandwidth for transmission. It also allows the probe to react quickly to unexpected findings, such as plumes or surface changes.

5. Starship deep-space tests

SpaceX plans to use AI-based guidance and diagnostics for Starship deep-space missions, with major test flights expected after 2025. Starship’s AI will assist with autonomous orbital adjustment, heat shield diagnostics, and landing maneuvers. These capabilities are designed to support future Mars flights and commercial lunar cargo delivery. AI will also monitor system performance during flight, detecting anomalies and rerouting power or thrust as needed. This level of autonomy reduces reliance on ground control, especially during high-risk phases like atmospheric entry and landing.

These missions reflect a growing shift toward AI-managed exploration. Each one reduces human dependence and builds the foundation for scalable, autonomous operations across the solar system.

Future Directions

AI already drives spacecraft, guides rovers, and processes mountains of data far beyond human reach. The missions launching from 2025 onward will show how far autonomous systems can take us – to the Moon, Mars, and the outer planets. As agencies and private companies invest in AI-managed construction, navigation, and discovery, they set the stage for a future where machines extend our senses and decisions across the solar system. The future of AI in space depends on innovation, global collaboration, and the resolve to use these powerful tools responsibly.

Related Links

Space Technology News – Applications and Research

The University of Arizona News published this story on July 15, 2025. Edits by EarthSky.

Meteor Crater and Grand Canyon connection?

Two world-famous attractions in the U.S. state of Arizona – the Grand Canyon and Meteor Crater – might share a hidden connection, according to new research from the University of Arizona and the University of New Mexico.

An international research team presented the results of its investigation this week (on July 15, 2025), in the peer-reviewed journal Geology. They described an intriguing “detective story” that has played out over several decades and across scientific disciplines. The team is proposing that the meteorite impact just west of Winslow, Arizona – which created Meteor Crater some 56,000 years ago and only 118 miles away – might have triggered a massive landslide that dammed the Colorado River and created an ancient lake 50 miles long and nearly 300 feet deep.

The journal Geology published this idea on July 15, 2025. Chris Baisan, a senior research specialist at the U of A Laboratory for Tree-Ring Research, said:

It is important to understand the effects of meteor impacts on the Earth, such as the one that contributed to the extinction of the dinosaurs, and we think we found a link between the strike that created Meteor Crater and a paleolake in the Grand Canyon that formed at the same time.

Baisan is a co-lead author on the study with Karl Karlstrom from the University of New Mexico.

Driftwood and lake sediments have been long known in a cave called Stanton’s Cave in Marble Canyon of eastern Grand Canyon.

The mouth of the cave is 150 feet above the river, so the detective story has been to figure out how and when did the driftwood got there?

Karlstrom, a distinguished professor emeritus at UNM in Albuquerque, said:

It would have required a 10 times bigger flood level than any flood that has happened in the past several thousand years.

A decades-long investigation

In the 1980s, Richard Hereford of the U.S. Geological Survey in Flagstaff and one of the paper’s co-authors, presented evidence of a rockslide near Nankoweap Canyon at river mile 52, about 22 river miles downstream of Stanton’s Cave, that might have formed a dam and a paleolake that allowed driftwood to float into the cave.

The driftwood was first excavated and radiocarbon dated in 1970, suggesting it was older than 35,000 years. Technological advances allowed for subsequent refinement of the dating accuracy, allowing researchers to increase their confidence in the results over time. In 2019, using state of the art equipment, Jonathan Palmer, one of the paper’s co-authors from the University of New South Wales in Sydney who specializes on dating extremely ancient samples, found the driftwood to date back to about 55,000 years.

As with many detective stories, chance and coincidence loom large in this one, too. During a visit to the U of A’s Tree-Ring Lab, where Baisan had been serendipitously working on the Stanton Cave driftwood collections, Palmer, went on a road trip and stopped at Meteor Crater.

The date of the impact – 50,000 years – caught his attention. Could there be a link between the two events? Baisan said:

Now there was this question, completely out of the blue, that nobody had asked before. And it just happened because of people from different parts of the world happened to visit each other.

Samples from another site, downstream

The scientists wrote a draft paper proposing the link, but the evidence seemed mainly circumstantial, and the presence of the rockfall dam and paleolake was not universally accepted. The draft was sent to Karlstrom, an expert on Grand Canyon geomorphology, for review and comment.

Together with the paper’s senior author, Laura Crossey, a distinguished professor at UNM, Karlstrom managed to locate and collect sediment and wood samples from an additional site downstream from the cave at roughly the same height above the river. Dating the two independent sample sets – wood and sediments – revealed the same age for both: 55,600 years, providing strong support for this study.

The paper also reports findings from two places where the chaotically deposited dam material at Nankoweap Canyon is overlain by river cobbles deposited as the river over-topped the dam and began to erode it. This process likely would have lasted less than 1,000 years based on analogies to modern concrete dams are filling up with sediment, according to the authors.

The paper also reports findings from two places where the chaotically deposited dam material at Nankoweap Canyon is overlain by river cobbles deposited as the river over-topped the dam and began to erode it. This process likely would have lasted less than 1,000 years based on analogies to modern concrete dams are filling up with sediment, according to the authors.

Grand Canyon mystery solved?

The crucial question of any detective story is, of course: “Who dunnit?” In this case, was the Meteor Crater impact enough to cause such a landslide? Meteor Crater Science Coordinator David Kring, calculated that the earthquake set off by the 300,000-ton nickel-iron meteorite would have reached magnitude 5.4 or even 6 on the Richter scale. Traveling the 100 miles to the Grand Canyon in a matter of seconds, the shock wave would still have packed a punch of an estimated 3.5 – 4.1 magnitude once it arrived. Baisan said:

We don’t know exactly what the ground shaking intensity was. There would have been the shock wave as the object passes through the air, then the blast wave, and finally the impact, which might have been enough to trigger a landslide in the canyon.

While the exact path and altitude of the meteor are not known, the authors deem it plausible that the triple effect was enough to shake loose portions of the canyon’s steep cliffs that were “waiting and ready to go.” While rockfalls are a common occurrence in the Grand Canyon, events with the capability to dam the river and create a lake, such as the Nankoweap rockfall, are exceedingly rare. Karlstrom said:

We put together these arguments without claiming we have final proof. There are other possibilities, such as a random rockfall or local earthquake within a thousand years of the Meteor Crater impact that could have happened independently.

Nevertheless, the meteorite impact, the massive landslide, the lake deposits and the driftwood high above river level are all rare and unusual occurrences.

Bottom line: Two world-famous Arizona attractions – the Grand Canyon and Meteor Crater Natural Landmark – might share a hidden connection.

Source (Geology, July 15, 2025): Grand Canyon landslide-dam and paleolake triggered by the Meteor Crater impact at 56 ka

Via University of Arizona

“The skies 41,000 years ago may have been both spectacular and threatening. When we realized this, we wanted to know whether this could have affected people living at the time,” the study authors said.

How did the skies influence early human lifestyle?

The study began with a simple but interesting question. What happens to life on Earth when the magnetic field nearly disappears? To find the answer to this question, the study authors combined climate models and archaeological evidence.

Their focus was the Laschamps Excursion, a brief but extreme event around 41,000 years ago when Earth’s magnetic field weakened drastically. Instead of its usual structure, like a giant bar magnet with a north and south pole, the magnetic field fractured into multiple weak poles scattered around the globe.

At its lowest point, the field strength fell to below 10 percent of today’s levels, leaving Earth exposed to dangerous cosmic radiation and solar winds. Usually, the magnetosphere acts as a protective bubble, shielding us from harmful ultraviolet (UV) rays and charged particles from the Sun.

However, during the Laschamps Excursion, that shield broke down. As a result, auroras that are normally seen only near the poles may have danced across much of the sky, and harmful UV radiation could have penetrated to Earth’s surface at far greater levels than usual.

While this sounds like a scenario from science fiction, it had real and potentially serious consequences for life. Increased UV exposure could have led to sunburn, eye damage, birth defects, and skin diseases. So the researchers asked, could ancient humans have noticed and adapted? The archaeological record provides some interesting clues.

Around this time, evidence shows a rise in the use of deep caves for shelter, the application of ochre-based pigments on skin, and possibly more protective clothing in parts of Europe where the effects would have been strongest.

All these behaviors could have helped shield early humans, both Homo sapiens and Neanderthals, from the sudden spike in solar radiation. However, the researchers are not claiming that the Laschamps Excursion caused Neanderthal extinction or major evolutionary changes of that time on its own.

“We’re not suggesting that space weather alone caused an increase in these behaviors or, certainly, that the Laschamps caused Neanderthals to go extinct, which is one misinterpretation of our research. But it could have been a contributing factor, an invisible but powerful force that influenced innovation and adaptability,” the study author said.

Chinese researchers say they’ve devised a new way to extract water from lunar soil and convert it into fuel.

As detailed in a new paper published today in the journal Joule, the team found that their proposed “photothermal strategy” — essentially converting light into heat — could effectively convert carbon dioxide from extracted water into carbon monoxide, hydrogen, and oxygen gas, a “potential route for sustaining human life on the Moon and enabling long-term extraterrestrial exploration.”

“The sustainable utilization of local resources is essential for long-term human survival on the Moon and beyond,” the researchers write, pointing out that bringing water from Earth is cost-prohibitive at roughly $83,000 per gallon.

“We never fully imagined the ‘magic’ that the lunar soil possessed,” said Chinese University of Hong Kong, Shenzhen professor and coauthor Lu Wang in a statement.

“The biggest surprise for us was the tangible success of this integrated approach,” he added. “The one-step integration of lunar H2O extraction and photothermal CO2 catalysis could enhance energy utilization efficiency and decrease the cost and complexity of infrastructure development.”

While plenty of questions remain about our future efforts to harness local resources on the surface of the Moon, it’s a glimmer of hope that humanity could indeed establish a more permanent and potentially sustainable presence there.

For their research, the team focused on simplifying existing proposals for how to extract water from lunar regolith, which tend to be energy-intensive and stop short of breaking the water down into its usable elements.

The researchers also propose using the extracted water to turn carbon dioxide exhaled by astronauts into carbon monoxide and hydrogen gas, which could be used to make fuels.

The team tested their photothermal approach on actual Moon samples gathered during China’s Chang’E-5 mission, which launched in November 2020, and collected samples from the northwest of the Moon’s near side before returning to Earth.

While their lab-based experiments turned out to be a success, the actual lunar surface will likely prove a far more challenging place to extract and convert lunar water. As the paper points out, radiation, low gravity, and extreme temperature fluctuations could complicate matters significantly.

However, the advancements highlight how far the Chinese space program has come in a matter of years. A mere two decades ago, China was a distant underdog in the international space race. But now that the country is launching its own astronauts to space while the Trump administration is effectively looking to eviscerate NASA when it comes to space science, China could stand a chance to surpass the US in its plans to build a Moon base by 2035.

More on extracting lunar water: Chinese Scientists Extract Water From Lunar Soil

FROM roiling storms, rare comets and volcanic eruptions, there is lots to see aboard the International Space Station (ISS).

Fortunately, astronauts are not only equipped with suites of scientific instruments, but cameras too – so we at home can enjoy the view as well.

7

Lightning sprite

Nasa astronaut Nichole Ayers caught a phenomenon known as a sprite near the Texas-Mexico border from the ISS, some 250 miles above Earth.

“Just. Wow. As we went over Mexico and the US this morning, I caught this sprite,” Ayers wrote on X earlier this month.

“Sprites are TLEs or Transient Luminous Events, that happen above the clouds and are triggered by intense electrical activity in the thunderstorms below.

“We have a great view above the clouds, so scientists can use these types of pictures to better understand the formation, characteristics, and relationship of TLEs to thunderstorms.”

Ayers snapped the picture with a Nikon Z9 using a 50mm lens (f/1.2, ¼ sec, ISO 6400) as part of a time-lapse set up in the Cupola – the domed window module on board the ISS.

“It takes planning, timing, and a lot of pictures to capture such a rare phenomenon,” she added.

7

7

Once-in-a-lifetime comet

Comet C/2023 A3 Tsuchinshan-ATLAS – dubbed the ‘once-in-a-lifetime comet’ – was photographed by Nasa astronaut Don Pettit from the ISS last autumn.

Scientists at the Royal Astronomical Society dubbed it the “comet of the century” because of its brightness and rarity.

The icy comet won’t be visible on Earth again for another 80,000 years – making the sighting particularly rare.

7

Aurora meets airglow

Nasa astronaut Scott Kelly and European Space Agency (ESA) astronaut Tim Peake shared this snap or aurora – or Northern Lights – dancing near Earth’s airglow in 2016.

In his whopping 340 days in space, Kelly was able to provide some stunning images of Earth seen from above.

These are two of Earth’s most colorful upper atmospheric phenomena.

The wavy green, red-topped wisps of aurora borealis appear to intersect the faint red-yellow band of airglow.

Though they appear at similar altitudes, aurora and airglow are different.

Nighttime airglow – also known as nightglow – is a type of chemiluminescence that occurs all around the Earth, all the time.

This is where light is emitted from chemical interactions between oxygen, nitrogen, and other molecules in the upper atmosphere.

Auroras, on the other hand, are caused by charged solar particles colliding with Earth’s atmosphere.

7

‘Devil horned’ volcano

While technically snapped by data visualisers at Nasa’s Earth Observatory, this “devilish” Russian volcano was captured spitting out a 1,000-mile-long stream of smoke into Earth’s atmosphere.

The striking image was snapped by Nasa’s Aqua satellite between June 22 and Dec. 31, 2023.

It was during an active eruption phase of the volcano, known as Klyuchevskoy or sometimes Klyuchevskaya Sopka – an area home to more than 300 volcanoes.

The two-pronged devil horns depict twin lava flows spewing out of the volcanoes mouth.

7

Spacewalk

The ISS has been orbiting Earth for nearly three decades, after first launching in November 1998.

Astronauts have conducted 275 spacewalks since the station opened – one of the riskiest jobs an astronaut will ever undertake.

Backdropped by New Zealand and the Cook Strait in the Pacific Ocean, astronauts Robert Curbeam and Christer Fuglesang participate in an extravehicular activity, December 12, 2006.

Their job was to support the construction of the orbital outpost, and proved the source of quite the stellar image.

7

Ganges river

The Ganges river, the world’s largest river delta, was photographed in near-infrared from the ISS by Pettit.

The ISS utilises near-infrared imagery for various scientific purposes, including atmospheric studies and Earth observation. 

It is key to capturing images of the Earth’s airglow, clouds, and other surface features during nighttime.

The end result are incredible false-colour images that show Earth in a completely new light.

False-color images combine and rearrange colour channels from multiple sources to visualise new details.

These details are either things that cannot be seen by the human eye – or aspects that may be obscured in true colour images, such as healthy vegetation or different soil types. 

 

An international team led by researchers from Monash University in Australia has developed a new model for thermosensing plants that redefines previously held theories about how plants sense and respond to temperature.

Their findings, published in the journal Science, explain that instead of using a single “thermometer” to sense temperature, like humans do, plants have a decentralized genetic network of proteins and biological processes.

A changing climate has already affected crop yields and plant health, which makes this shift in perspective about how plants deal with temperature shifts extremely useful.

“Understanding how plants naturally integrate temperature into their growth and defence systems opens the door to precision breeding and AI-assisted approaches to enhance crop resilience,” said lead researcher Professor Sureshkumar Balasubramanian.

“Effectively, this means we can grow designer crops that are tailored to the local climate of a particular region.”

A United Nations report has warned that in the next 30 years, food supplies and food security could be threatened by the negative impacts of a warming planet. Action needs to be taken to mitigate the effects and bolster the food system’s resilience.

Watch now: How bad is a gas stove for your home’s indoor air quality?

There have been various advancements in helping plants deal with these climate shifts, including using zinc to protect plants from heat and slowing down the plant aging process through genetic engineering.

Around a decade’s worth of research into farming practices has shown that reduced tilling and more varied crops can help soil retain more nitrogen, which is essential to growth.

Sorghum, which is a naturally resistant cereal grain, is being studied to better understand its molecular structure, which could help improve breeding practices for other plants.

The results of this new comprehensive review about how plants sense temperatures can offer solutions to a broad range of plant species across different regions. This could help farmers breed resilient crops specifically tailored to their locality.

“Now that we have been able to identify exactly which elements within the plants are temperature-responsive, we can genetically manipulate them with greater accuracy,” said Dr Sridevi Sureshkumar.

“We can determine the specific combinations of manipulations that can produce bespoke solutions. Think of it like personalised medicine but for plants; this will revolutionize the way we think about agriculture moving forward.”

Join our free newsletter for weekly updates on the latest innovations improving our lives and shaping our future, and don’t miss this cool list of easy ways to help yourself while helping the planet.

The world of Bousso’s new theorem still departs from our universe in notable ways. For mathematical convenience, he assumed that there’s an unlimited variety of particles—an unrealistic assumption that makes some physicists wonder whether this third layer matches reality (with its 17 or so known particles) any better than the second layer does. “We don’t have an infinite number of quantum fields,” said Edgar Shaghoulian, a physicist at the University of California, Santa Cruz.

Still, for some experts, Bousso’s work delivers a satisfying denouement to the Penrose and Wall singularity story, despite its unrealistic abundance of particles. It establishes that singularities can’t be avoided, even in space-times with mild reactions to quantum matter. “Just by adding small quantum corrections, you can’t prevent the singularity,” Penington said. Wall and Bousso’s work “answers that pretty definitively.”

The Real Singularity

But Bousso’s theorem still doesn’t guarantee that singularities must form in our universe.

Some physicists hold out hope that the dead ends do somehow go away. What seems like a singularity could actually connect to somewhere else. In the case of a black hole, perhaps those light rays end up in another universe.

And a lack of a Big Bang singularity might imply that our universe began with a “Big Bounce.” The idea is that a previous universe, as it collapsed under the pull of gravity, somehow dodged the formation of a singularity and instead bounced into a period of expansion. Physicists who are developing bounce theories often work in the second layer of the onion, using semiclassical physics that exploits negative-energy quantum effects to get around the singularity required by the Penrose and Hawking theorems. In light of the newer theorems, they will now need to swallow the uncomfortable truth that their theories violate the generalized second law as well.

One physicist pursuing bounces, Surjeet Rajendran of Johns Hopkins University, says he is undaunted. He points out that not even the generalized second law is gospel truth. Rejecting it would make singularities avoidable and continuations of space-time possible.

Singularity skeptics can also appeal to the theory at the core of the onion, where space-time behaves in truly quantum ways, such as taking on superpositions. There, nothing can be taken for granted. It becomes hard to define the concept of area, for instance, so it’s not clear what form the second law should take, and therefore the new theorems won’t hold.

Bousso and like-minded physicists, however, suspect that a highly quantum arena with no notion of area is tantamount to a dead-end for a light ray, and therefore that something Penrose would recognize as a singularity should persist in the core theory and in our universe. The beginning of the cosmos and the hearts of black holes would truly mark edges of the map where clocks can’t tick and space stops.

“Inside of black holes, I am positive there is some notion of singularity,” said Netta Engelhardt, a physicist at MIT who has worked with Wall.

In that case, the still-unknown fundamental theory of quantum gravity would not kill singularities but demystify them. This truer theory would allow physicists to ask questions and calculate meaningful answers, but the language of those questions and answers would change dramatically. Space-time quantities like position, curvature and duration might be useless for describing a singularity. There, where time ends, other quantities or concepts might have to take their place. “If you had to make me guess,” Penington said, “whatever quantum state describes the singularity itself does not have a notion of time.”

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Original story reprinted with permission from Quanta Magazine, an editorially independent publication of the Simons Foundation whose mission is to enhance public understanding of science by covering research developments and trends in mathematics and the physical and life sciences.

Images of the new interstellar object 3I/ATLAS (posted in papers here, here, here and here) show a slight elongation along its direction of motion. However, the elongation beyond the angular width of background stars (the so-called `point spread function’) is exactly at the level expected from multiplying the object’s speed of 60 kilometers per second by the exposure time of the telescope of about a hundred seconds. This elongation is not mitigated by freezing the object’s image and letting the background stars move relative to it. It results from the fact that a single snapshot of the image takes a hundred seconds. The product of this exposure time and the speed of 3I/ATLAS yields a scale of order 6,000 kilometers (comparable to Earth’s radius), extending over an angle of ~2 arcseconds in the sky given the object’s distance of 4.5 times the Earth-Sun separation. While 3I/ATLAS may well be a comet, this elongation should not be taken as evidence for its cometary tail. So far, spectroscopic data on 3I/ATLAS (published here, here and here) do not reveal the spectral features of cometary gas but only show reddening of reflected sunlight, consistent with a compact dust cloud or the surface of a solid object.

The brightness of 3I/ATLAS implies a diameter of 20 kilometers for an asteroid with a typical reflectance (albedo) of 5%. As I showed in a published paper shortly after 3I/ATLAS was discovered, the detection of this object over 5 years of the ATLAS telescope’s survey of the sky, requires an untenable mass supply of rocky material from the Milky-Way galaxy. If 3I/ATLAS is 20 kilometers in diameter, it might have targeted the inner Solar System as expected from alien technology. This possibility was discussed in a follow-up paper that I wrote with Adam Hibberd and Adam Crowl, where we highlighted the anomalous properties of the trajectory taken by 3I/ATLAS.

Indeed, the simplest interpretation that I provided in my paper is that 3I/ATLAS is an extended dust cloud with a cometary nucleus that is smaller than a kilometer in size. But it is worth contemplating alternatives in case future data will indicate a much larger solid object. Resistance to multiple interpretations and bullying those who suggest them is anti-scientific.

There is another lesson to be learned from the elongation in the images of 3I/ATLAS. Imagine a spacecraft moving a hundred times faster than 3I/ATLAS, at 6,000 kilometers per second. This corresponds to 2% of the speed of light, an order of magnitude lower than the goal of the Breakthrough Starshot Initiative, which I led over the past decade. If humans dream of launching a spacecraft at 20% of the speed of light only a century after the discovery of quantum mechanics and general relativity, why would aliens — who might have enjoyed the benefits of many millennia of science, not aim to launch spacecraft at 2% of the speed of light?

Unfortunately, our existing telescopes would not alert us to a spacecraft moving that fast because the spacecraft image would be smeared into a faint line that would be missed by observers, given the background of scattered light from the Sun and the Milky Way. If 3I/ATLAS was moving at 2% of the speed of light, then over a 100 seconds exposure, its image would have been smeared to a faint line, spreading its light over a length of a few arcminutes and making its surface brightness too small to be detectable even with our largest telescopes.

In other words, we are blind to spacecraft moving ten times slower than our own most ambitious technological goal in the context of Breakthrough Starshot.

In case relativistic spacecraft are flying through the Solar System, the answer to Enrico Fermi’s question: “where is everybody?” is “perhaps right here, but we are blind to them.” This blindness has nothing to do with stealth technologies or new physics that the aliens employ. The images of near-Earth relativistic spacecraft would be smeared to undetectable brightness levels even if they were to reflect sunlight like asteroids that are 20 kilometers in diameter, twice as large as the Chicxulub impactor that killed the non-avian dinosaurs on Earth 66 million years ago.

With better technologies, we can overcome this blindness. For example, the above limitations hold for observatories sensitive to light. In addition to those, the National Science Foundation also funded the Laser Interferometer Gravitational Wave Observatory (LIGO) which detects gravitational signals at a frequency of order 100 Hertz. In a paper published last year, I showed that LIGO is sensitive to the tidal gravitational signal from relativistic interstellar objects on the scale of tens of kilometers as long as they pass within a distance comparable to Earth’s radius. Since no unusual signal with the time profile that I calculated was reported by LIGO so far, we can conclude that no massive relativistic object passed near Earth over the past decade. Unfortunately, we cannot say much about larger distances, because the gravitational tidal signal would have been weaker than LIGO’s sensitivity.

It comes as no surprise that what we perceive as the observable Universe is limited by the sensitivity of our instruments. It is indeed the case that 95% of the cosmic mass budget is unknown. Nobel prizes were awarded to observers who exposed our ignorance about the unknown cosmic constituents, even though it would have been far more satisfying to know what dark matter and dark energy are. Given this backdrop, mainstream astronomers and SETI advocates must pause before claiming that the existence of aliens is an extraordinary claim that requires extraordinary evidence. It may well be an ordinary claim that requires ordinary evidence, but we fail to find this evidence because of our limited detector sensitivity.

ABOUT THE AUTHOR

Avi Loeb is the head of the Galileo Project, founding director of Harvard University’s — Black Hole Initiative, director of the Institute for Theory and Computation at the Harvard-Smithsonian Center for Astrophysics, and the former chair of the astronomy department at Harvard University (2011–2020). He is a former member of the President’s Council of Advisors on Science and Technology and a former chair of the Board on Physics and Astronomy of the National Academies. He is the bestselling author of “Extraterrestrial: The First Sign of Intelligent Life Beyond Earth” and a co-author of the textbook “Life in the Cosmos”, both published in 2021. The paperback edition of his new book, titled “Interstellar”, was published in August 2024.