Hours of research by our editors, distilled into minutes of clarity.
In the 17th century, Galileo's observations suggested the moon could be inhabited, leading to fictional speculations about lunar life. In the 19th century, stories were published claiming the discovery of various creatures, including human-bats. The Apollo missions in the 20th century explored the possibility of life there, but further exploration showed this idea to be less likely than before.
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.
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.
Around 50 BCE, Roman poet and philosopher Lucretius shared Greek philosopher Epicurus’s ideas about the potential of alien life. The writing is believed to be the first straightforward assertion in Western literature that aliens must exist.
The Pentagon made a splash in recent years with revelations of videos showing fighter pilots observing unknown aerial objects. Lindsey uncovers stories of still-unverified UFO sightings and addresses the likely possibility of life beyond Earth.
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.
Three experiments on the Viking 1 and 2 landers searched for signs of metabolic activity in soil samples, indicating the presence of microorganisms. No definitive evidence of life was found in any experiment or lander imaging.
The 21st century has introduced advances making telescopes, cameras, and computers powerful enough to detect the presence of molecules associated with biological processes in distant atmospheres, expanding the search for life to include unreachable worlds.
The field incorporates observational missions to find and classify exoplanets—planets orbiting stars besides the sun—the probing of Earth's most extreme environments to learn what conditions allow life to exist, and theoretical and lab work to identify and analyze potential biochemical signatures.
Recovered from Antarctica in 1984, ALH84001 contained organic compounds, magnetite and iron sulfide grains of potential biological origin, and features that resembled fossilized bacteria. With technological advancements, scientists found abiotic origins for these features in the following decades.