Researchers on extraterrestrials: Why real aliens are unlikely to look like our familiar 'little green men'

Current research, however, paints a very different picture.

Spaceship, flying saucer, oversized eyes, green skin - the cliché runs so deep that many people no longer stop to ask how physically or biologically plausible such beings would actually be. Speak to astrobiologists, astronomers, or psychologists and it quickly becomes clear: the famous “little green men” mainly reveal something about us - and very little about real life beyond Earth.

How the green alien image took hold

The idea predates the modern UFO wave. Early science fiction used visitors from elsewhere as a screen onto which fears and hopes could be projected. In the 1950s, the theme received a huge boost: newspapers ran stories about supposed encounters, and radio and television eagerly amplified them. Headlines needed a punchy visual - and bright, small figures fitted perfectly.

What’s striking is that many accounts of alleged sightings described wildly different shapes and colours. Some witnesses reported grey figures, others spoke of glowing lights, and others still mentioned only shadows. Even so, the small green figure won out, because it kept reappearing in films, comics, and pulp magazines.

“The stereotype of the little green man is less an eyewitness account than a media product - amplified by decades of science fiction.”

Pop culture and “little green men” aliens shape what we expect to see

As cinema became a dominant mass medium in the 20th century, the alien turned into a mainstream character: sometimes a threat from the stars, sometimes a warning messenger, sometimes a comic sidekick. Franchises such as “Star Trek” and major film classics established a template: humanoid bodies, readable faces, recognisable emotions.

There’s a simple reason for this. People find it easier to empathise with beings that resemble them at least loosely. An alien with arms, legs, and eyes is far easier to film, apply make-up to, and animate than an utterly unfamiliar lifeform made of gas, plasma, or microbes. A feedback loop forms:

• Science fiction creates visually simple aliens - often green, often human-like.
• Audiences become used to the look and start to treat it as “typical”.
• New films and series reuse the same image because it is instantly recognisable.

This has little to do with scientific expectations. It’s more of a cultural code: the alien represents the “other” - and that otherness is meant to be obvious at first glance.

Why green, specifically? The psychology behind the colour

The colour choice isn’t random. In nature, green is ambiguous. On the one hand it suggests plants, vitality, and growth. On the other, it can signal warning - as with certain insects, frogs, or mould, where green implies poison, illness, or danger. That tension is precisely what makes green appealing in stories about unfamiliar life.

Psychologists see this as a neat shortcut: green skin instantly communicates “not from here” without lengthy explanation. Viewers intuitively sense something is off - alert, unfamiliar - but not necessarily deadly. That makes room for a wide range of roles:

• cute, almost childlike characters you can laugh at,
• mysterious observers whose motives remain unclear,
• threatening invaders with superior technology.

Small stature works in a similar way. Smaller beings feel less intimidating at first. They’re easier to make endearing, while stories can still grant them extreme abilities - telepathy, exceptional intelligence, futuristic technology. That push-and-pull keeps the trope engaging.

What researchers now consider more likely

Anyone working in astrobiology tends to describe a far more sober outlook. Most specialists expect that the first confirmed discovery of life beyond Earth will look unimpressive - at least by Hollywood standards.

From microbes to completely unfamiliar intelligence

Examples of realistic scenarios researchers discuss include:

• Microbial life - simple bacteria or similar organisms in underground oceans on icy moons or on exoplanets.
• Chemical traces - gases in distant atmospheres that are best explained by biological activity.
• Unknown biochemistry - life that doesn’t rely on Earth-like DNA, instead using different molecules.
• Technological signals - radio transmissions, laser flashes, or mega-structures in space indicating a highly advanced civilisation.

All of these possibilities share one thing: they are very unlikely to resemble little green people. Even on Earth, life varies enormously - from deep-sea worms to fungal networks to viruses. So why would the Universe produce a figure that looks so much like us?

“Many scenarios researchers talk about do without bodies, eyes, or faces entirely - they think in terms of chemical signatures, energy flows, and evolutionary pathways.”

Why the cliché refuses to go away

Despite growing streams of data from space telescopes, Mars rovers, and probes, the image of the green alien remains stubbornly resilient. That’s because it has strong symbolic power. In a world where governments release secret UFO reports and alleged “alien bodies” are displayed in parliaments, the public reaches for simple images to cope with uncertainty.

The little green figure bundles several things at once:

• the question of whether we are alone in the Universe,
• fear of the unknown and of losing control,
• hope for superior technology and answers to big mysteries,
• a dose of humour that makes the topic bearable.

Because of this combination, the alien can be used in chat shows, memes, series, and advertising without having to explain complex research every time. The symbol is immediately legible - almost like a logo for “anything not from Earth”.

What real research is doing in practice

While pop culture clings to the green character, researchers work with far more down-to-earth tools. Key approaches include:

Field	Aim
Exoplanet research	Identify planets where liquid water could exist and whose atmospheres contain striking gases.
Missions to moons	Search icy moons such as Europa or Enceladus for traces of microbes in underground oceans.
SETI projects	Detect signals that cannot be explained by natural processes.
Laboratory experiments	Study how chemistry can produce complex molecules and the first building blocks of life.

From the outside this work can look uneventful, but it provides the pieces needed to assess - seriously - how likely life in the cosmos may be.

Why we cling to the myths

Our fascination with unfamiliar beings runs deeper than entertainment. It forces us to think about ourselves. When we ask what extraterrestrial intelligence might look like, we automatically raise questions such as: what counts as intelligence? What is consciousness? What role does morality play when we consider entirely different life histories?

In that sense, little green men function as a mirror. They embody hopes of rescue through superior technology, but also fears that we might one day be a primitive species judged by others. By telling stories about visitors from elsewhere, we negotiate power, responsibility, and humanity’s capacity to shape its own future.

Anyone who digs into the subject soon encounters specialist terms that rarely appear in everyday language. “Biosignatures”, for example, refers to any measurable traces that could indicate life - from particular gases in an exoplanet’s atmosphere to unusual patterns in the light from a distant world. These ideas may sound abstract, but they have concrete consequences: they influence where telescopes look and which instruments space probes carry.

For your own imagination, it can help to let go of the fixed notion that aliens must have two arms, two legs, and a head. Even considering what an intelligence might be like if it evolved inside a dense gas giant, or emerged in an ammonia-rich environment, opens up new lines of thought. Little green men were a useful gateway into fantasy; the real search for life beyond Earth begins where we deliberately set those familiar images aside.