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

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

The writer behind Mindless Algorithm, George McGowan, challenges various assumptions about aliens depicted in science fiction. One of those is that aliens are, like humans, individual entities that live, age, and die. McGowan suggests that the difficulty of intergalactic travel and the aliens' technological advancements make it more likely that they'd be an advanced form of AI or digital copies of biological entities.

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.

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.

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.

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.

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.

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.

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.

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.

Lining up every microbe on Earth would stretch to about 105,000 light-years

There are about 10²⁷ such organisms on the planet, many of which are adapted to produce energy through uncommon reactions in unconventional environments, such as within rocks or near volcanoes on the ocean floor. Studies of these organisms have reframed astrobiologists' search for life beyond Earth by broadening the parameters under which life can exist.

Mold growth in space raises the hypothesis of life being brought to Earth

Panspermia suggests that life could be carried throughout the cosmos by asteroids, comets, and other objects, but it requires organisms that can withstand the extreme cold of space travel, stellar radiation, lack of water, and intense heat of planetary impacts. The discovery of mold on the International Space Station and experiments showing it can withstand radiation in outer space-like conditions increase the plausibility of the hypothesis.

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.

Drugs in space: the pharmacy orbiting the Earth

Researchers are developing pharmaceutical solutions for astronauts, whose bodies may not respond the same way in space as they would on Earth. Similar to how microgravity causes changes to astronaut physiology, the environmental shift enables new...

The inhabitability of the Martian environment presents significant colonization risks

Terraforming the thin atmosphere, toxic dust, extreme cold, and lack of magnetic field is infeasible, given limitations to the size of what can be sent to Mars. NASA and SpaceX are instead exploring creating underground shelters.

Blood evolved many times over hundreds of millions of years

The earliest evidence of a blood-like substance comes from ancient arthropods, which appear to have had copper-based blood. In the 500 million years since then, some creatures have grown to rely on other variants, such as humanity's iron-based blood.

Environment and genetics explain why animals have widely different lifespans

Both environmental conditions and genetic factors shape how long various animals live. For some creatures, colder conditions allow for less energy use and slower aging. Larger animals have fewer predators. While humans don't live the longest, we are a rare species that successfully lengthened its average lifespan over time.

Why scientists are making robot insects

Insects have much to teach us about flying, jumping, moving quickly, and more. So, roboticists are studying how insects do the ridiculous things they do, like walk on water or jump fifty times their body height, to inform their design and engineering of a new slate of robots: tiny ones. Learn the future of this type of robot with this fascinating video with insights into both insects and robots.

A deep dive into how a body decomposes

Dead bodies are, understandably, scary and unsettling. Learn about the fascinating process of decomposition that takes place in every human, and how its teeming with life.

Biosphere 2 revealed limitations in maintaining wildlife in unfamiliar environments

Trees appeared to become weak and more prone to breaking because a lack of wind caused them to no longer need to develop stress wood. The extinction of pollinators—potentially due to an explosion in the population of longhorn crazy ants—was also unexpected.

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.'

Why portraits of Neanderthals vary so drastically

Neanderthals, humanity's long-lost genealogical cousins, are often portrayed as bumbling, hairy, cave-dwelling misogynists. But other efforts show tall, dignified creatures not too different from contemporary people. This article explores why most visual interpretations of Neanderthals are more in the service of social or political beliefs instead of science.

Humans may be the ultimate invasive species

Originating in East Africa, Homo sapiens migrated across the world beginning about 60,000 years ago and directly harmed countless species by consuming resources and modifying ecosystems to serve our needs. While meeting the definition of an invasive species, some ecologists argue the opposite, claiming that humans have helped preserve numerous species.

There are at least 6 fascinating examples of mind-controlling parasites

Parasitic organisms—including flatworms and barnacles, not just fungi—can modify animal behavior. They can give rise to dancing fish, pulsating snails, suicidal rats, and more. Though some of these pathogens can sicken humans, there is no strong evidence that any can control human behavior.

'The arts and sciences are avatars of human creativity. It's our attempt to influence things, the universe internal to ourselves and external to us.'

- Mae Jemison (1956-present), the first Black woman in space

Imagining if humans could perform photosynthesis and how it would change our anatomy

Since chloroplasts reflect green light, becoming photosynthetic would give our skin a green appearance. Because photosynthesis has efficiencies of only 5% to 9%, and humans burn 2,000 Calories daily compared to about 200 burned by a tree, becoming photosynthetic would also require us to adopt a less active, sun-filled lifestyle.

Humans experience the world subjectively. What does that mean for scientific research?

When you close your eyes, do you see static or colorful patterns or an "intrinsic grey" known as Eigengrau in German? This variation of our internal experiences is just the tip of the iceberg, one that scientists are increasingly studying and...

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

Explore the known asteroids, comets, and spacecraft involved in asteroid studies within our solar system with 'Eyes on Asteroids,' a 3D visualization from NASA.

Astronauts have repaired genetic damage in space using CRISPR—a molecular tool that can make precise changes to DNA and is used in single-celled organisms to attack invasive viruses.

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.

Larger animals like giraffes, elephants, and blue whales have developed a unique defense against cancer, a phenomenon known as Peto's Paradox

After 25 people used virtual reality headsets to practice flying with virtual wings—flapping their arms—their visual cortex responded to the wings almost as if they were real arms, treating them as body parts.

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.

See how each of the more than two million known species relates to each other—and to common ancestors—in this zoomable tree of life.

Animal phobias are likely the most common type of phobias, followed by an extreme fear of heights.

Learn how your body is, scientifically, like a firework with its own slow, controlled burn.

The first line of 'immortal' human cells, which can divide indefinitely and are used in scientific research, was nonconsensually taken from a Black woman.

Most of the observable universe's volume consists of voids and supervoids—enormous regions of space with little to no galaxies, stars, or light.

The American cockroach is actually from Africa, an apparent hitchhiker aboard ships carrying enslaved people, with evidence suggesting the bug may have arrived in the New World as early as the 1600s.

When you complete a CAPTCHA on a website to prove you are human, you may be unknowingly training algorithms for self-driving cars, whose systems require training data to help identify crosswalks, bicycles, and other outdoor objects.

Researchers believe the brain consolidates memories, processes emotions, and plans for the future during dream states

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.

About 2,000 US babies are born annually without some portion of their limbs, potentially leading to a lifetime of pricey prosthetics.

Watch how deep-sea mining equipment collects and processes polymetallic nodules—metal-rich, potato-shaped rocks—from the ocean floor and creates environmentally damaging plumes of sediments.

Objects can be 3D printed with light by projecting 2D computerized tomography (CT) scans onto rotating cylinders of resin, which solidify upon exposure.

Watch what the Ebola virus does inside our cells and organs in order to spread and survive.

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

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

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.

In 1963, a basement renovation in Turkey revealed a passageway to a hidden, multilevel underground city that once housed as many as 20,000 people