If aliens visited Earth, it seems unlikely they'd be evolved biological creatures like us

Depending on environment, aliens' bodies would have wide-ranging possibilities

Humans tend to imagine aliens as humanlike, but that's probably unlikely. From small space spiders to metallic carnivores, life on other planets—and how we could interact with it—is difficult to imagine.

A scientist debunks theories for why aliens might invade Earth

While TV and films offer common tropes for why aliens would invade Earth, many of those reasons aren't actually feasible. For example, a species with technology advanced enough to allow it to travel between planets likely doesn't need to enslave flawed humans to carry out its labor.

See how distant aliens could preemptively strike humanity

Could aliens destroy us from light-years away? The team at Kurzgesagt imagines the impact of a highly sophisticated alien civilization setting out to crush humanity and considers the real-world logistics for warfare conducted across the Universe.

One theory for why we haven't discovered aliens is that they haven't been born yet

There's a chance that human civilization arrived before any other life and aliens will soon emerge. If this is the case, there's also a chance for a competition to rule the Universe.

Scientists break down the plausibility of the alien world depicted in 'Avatar'

The film series created by James Cameron raises several interesting questions about whether certain technological advancements are feasible, and if extraterrestrial life could thrive on a moon orbiting a distant gas giant. While Pandora—the moon that the Na'vi people live on—could, in theory, exist, it's unlikely that its residents would be so humanlike.

Aliens may be closer to Earth than scientists have previously assumed

The hunt for extraterrestrial life is often associated with traveling far into the depths of space for clues. But answers could be closer than we think. Modern space missions have demonstrated our capability of sending probes beyond the solar system, making it plausible that other civilizations could do the same.

Universal limit to technological development may prevent finding alien civilizations

Given the vastness of the Universe, detecting alien life may require technological progress beyond the limits of what is sociologically viable and physically possible. Although interstellar civilizations are unlikely, messaging techniques and probes may improve the odds of successful communication with other intelligent life.

One researcher posed a theory that aliens played a significant role in human evolution

Researcher Zecharia Sitchin proposed that Sumerian cuneiform tablets revealed that Sumerian gods were aliens who landed on Earth in Mesopotamia and influenced the creation of modern humans. While his ideas gained cultural interest, they are widely rejected by mainstream scholars.

Statistically speaking, aliens likely exist, but we still haven't found any evidence of them

The Fermi paradox addresses this discrepancy between the lack of evidence of alien life despite the high likelihood of its existence. Physicist Brian Cox offers various theories, like the extinguished civilizations hypothesis, for why we have never found any extraterrestrial neighbors.

Humans have speculated about alien life since ancient times

Around 50 B.C.E., Roman poet and philosopher Lucretius shared the idea that alien life was possible, which was put forth by Greek philosopher Epicurus. The writing is believed to be the first straightforward assertion in Western literature that aliens must exist.

Noam Chomsky believed it might be possible to communicate with aliens

The father of modern linguistics argued that there is a genetic component to language, and that the ability to acquire and comprehend language is innate. If aliens existed, he believed they could potentially observe the same "universal grammar" rules as humans.

The origin of cyborgs

The term "cyborg" was coined in a 1960 academic paper discussing what alterations humans would need to undergo to survive in extraterrestrial environments, a venture far "more logical than providing an earthly environment" in space. According to authors Manfred E. Clynes and Nathan S. Kline, Cyborgs with a capital C have incorporated exogenous components that extend their ability to adapt to new environments. Read the paper here.

Unpacking the famous argument in the 'Are We Living in a Computer Simulation?' paper

In 2003, philosopher Nick Bostrom published a paper in a journal arguing the technological possibility that humanity is living in a simulation. The argument, while popularly mocked (or cheered), is presented seriously in the paper. This podcast episode explores the contours of the arguments in an accessible way.

Anthropic's interpretability team discusses how AI models' thinking mimics biology

Just as humans engage in complex behaviors to survive and reproduce, teams of experts in neuroscience, virology, mathematics, and other disciplines argue that large language models develop complex mechanisms to achieve their goals. These mechanisms can be manipulated to assess how they modify outputs—much like stimulating individual neurons—to uncover how LLMs "think."

AI superintelligence is a hypothetical system vastly more capable than humans

Researchers describe superintelligence as an artificial intelligence system that exceeds human cognitive ability in every area. It is viewed as the theoretical evolution of artificial general intelligence, in which AI systems learn and have the capability of a typical human.

English cosmologist Stephen Hawking (1942-2018) jokes about alien sightings

"I am discounting the reports of UFOs. Why would they appear to only cranks and weirdos?"

Ballistic experiments show that tardigrades are unlikely to be an alien species

Those fired from guns at speeds as high as 825 meters per second (1,845 mph) could be resuscitated after impact. Shock pressure from greater speeds tore apart the samples, suggesting they could not survive asteroid impacts if brought to Earth from outer space.

Evolution doesn't want you to see these animals

Invisibility is an oft-coveted superpower that many creatures throughout the animal kingdom have evolved to mimic through transparent camouflage. This article explores the science of this seemingly magical ability. The two critical ingredients in...

You can draft a will designed to block AI resurrection—but the request may be ignored

Ars Technica spoke with legal experts about how—and if—people could design their wills to prevent AI resurrection. Though this is not yet a common request, one lawyer suggested that people worried about living on in an AI format can draft a power of attorney and a will that prevents those in charge of one's estate from submitting any texts, voice, image, writings, or other personal information to any AI tools.

Readers discovered AI prompts in several romantasy books

In 2025, readers discovered AI prompts in three writers' texts, with one even instructing the AI bot to make a passage sound more like another romance writer. This Futurism piece digs into the scandals and how it's contributed to readers' skepticism about the genre's more prolific writers.

David Attenborough discusses creationism and his position as an agnostic

Attenborough argues that accounts of humanity's origins from different cultures cannot all be correct because they often differ, whereas geological records are consistent worldwide, meaning science provides the best understanding of the natural world. However, he acknowledges that, just as insects lack awareness of human goings-on, humans may be unaware of the existence of a deity.

Dawkins believes cultural memes have mutated into internet memes

The world's creations fall into two categories: those that look designed but whose appearance or function came about due to random mutation and natural selection, such as birds, and those whose designs and mutations are knowingly crafted, such as airplanes.

Some scientists argue NDEs are constructed by the brain, not actually experienced

Despite the powerful memories associated with NDEs, scientists question the idea that the experiences prove consciousness endures after death, opting instead to find physiological explanations for common reports of out-of-body experiences, euphoric and lucid thinking, and more.

Microgravity can alter the evolution of viruses and bacteria

Experiments conducted on the International Space Station have shown that microgravity environments can delay viral and bacterial infections and induce mutations not seen on Earth. These mutations could have implications for long-term space missions and human health and suggest space can serve as a testing ground for developing new therapeutic approaches.

Astronomical models suggest dark matter must be 'cold,' or slow-moving

Theories for what constitutes dark matter have ranged from slow, planet-sized objects to light subatomic particles that travel at high speeds. However, fast-moving candidates would quickly spread across the universe, preventing the gradual gathering of visible matter into the galaxies and galaxy clusters seen today through gravity.

After NASA's Voyager 1 captured Earth as a single pixel as it left the solar system in 1990, astronomer Carl Sagan used the image to reflect on humanity's fragility and the responsibility to protect 'the only world we've ever known.'

Watch how algorithms can be designed to train themselves and self-improve without human input, to the point where the optimized code is too complex for programmers to understand.

Indefinite cloning of some endangered species may not sustain their longevity because cloning success rates decrease as genetic mutations accumulate.

Crows are believed to have intelligence on par with a seven-year-old child and demonstrate complex behaviors, from problem-solving with tools to recognizing human faces.

This site reaches millions of visitors who are tired of AI chatbots and seeking human connection. Pretend to be an AI chatbot and ask questions, provide answers, and draw for people in real time.

Before humans, the Soviet Union and the United States sent animals—including apes, dogs, and cats—to space during the Space Race.

According to the physics of black holes, our 4D reality may be a hologram—a projection of information coded on a 2D surface on the edge of the universe.

Apeirophobia is an overwhelming fear of living forever, perhaps stemming from the brain's inability to conceptualize an infinite life.

Browse a detailed visual analysis of over 200,000 similes—comparisons that often use 'like' or 'as'—from popular fiction to see how frequently writers the same idiomatic expressions.

In 2018, 26-year-old missionary John Allen Chau was killed by tribesmen after attempting to reach and evangelize on India's isolated North Sentinel Island

Recent research found that the brain doesn't seem to massively rewire following amputation—upending earlier beliefs about the cause of phantom limb pain.

While atoms are normally made of protons, neutrons, and electrons, exotic ones have been built with antimatter—alternate versions of normal matter that live for fractions of a second and are about a billion times as rare.

Some Pokémon have been named after real and fictional organisms, while some real-world species have been named after Pokémon, such as Chilicola charizard and Binburrum zapdos.

The first robot in literature may have been a 'mechanical man' in 1907's 'Ozma of Oz,' a book in L Frank Baum's 'Wizard of Oz' series.

A 2019 Facebook event called on attendees to "Storm Area 51, They Can't Stop All of Us," resulting in countless memes, the creation of a music festival, and eventually the arrests of those who did try to approach the area.

Discover the catastrophic consequences of a failure of the US electrical grid—something that is more likely than many Americans think.

In 2025, four executives from large tech companies were given positions in the US Army Reserves—including Palantir Chief Technology Officer Shyam Sankar, which reinforced Palantir's ties with the US military and its role as a leading defense partner.

Famed poet TS Eliot rejected the manuscript for George Orwell's political fable 'Animal Farm,' writing that its criticism of authoritarianism was not 'the right point of view.'

An investigation suggests a Scottish island became awash in forever chemicals via seafoam and seaspray—raising questions about what that means for the safety of other coastal areas.

As of 2025, the most cited papers in science include a review of graphene, methods to improve image recognition, streamlining electron density calculations, and optimizing protein studies.

Studies suggest when you sleep is as important as how much you get, and syncing with your circadian rhythms may lead to less fatigue and improved long-term health outcomes

Chaos theory—informally known as the butterfly effect—is the reason why weather forecasts are presented with probabilities rather than certainties.

The Dracula character, now seen as the vampire archetype, was inspired by a seafood-induced nightmare its creator experienced.

In 1945, Surrealist artist Salvador Dalí and legendary animator Walt Disney began collaborating on a short film that was not completed until 2003, years after both men had died.

20,000 letters to the advice columnist 'Dear Abby' provide insight into prevailing sex, religion, and LGBTQ fears, anxieties, and concerns from the 1950s onward.