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Has compelling evidence of extraterrestrial life been found?
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extraterrestrial life
An illustration of the Earth-size planet TOI 700e orbiting within the habitable zone of its star. The habitable zone is the area around a star where liquid water, and thus possibly life, can survive on a planet's surface. Its Earth-size sibling, TOI 700d, can be seen in the distance.
To date, no compelling evidence of extraterrestrial life has been found. While the search for life beyond Earth is a primary objective of astrobiology, all claims of discovery—including those involving meteorites or reports of unidentified flying objects—have either been attributed to contamination or remain unproven and scientifically unaccepted.1234
Despite the lack of direct evidence, the scientific community remains engaged in the search because the possibility of life elsewhere is supported by several factors:
- Habitable Environments: Discoveries suggest that liquid water—a key requirement for life as we know it—may exist in subsurface oceans on moons such as Europa and Enceladus.145
- Extremophiles: The existence of extremophiles on Earth demonstrates that life can thrive in extreme conditions, broadening the range of potentially habitable environments.1
- Abundance of Planets: The discovery of thousands of extrasolar planets indicates that planetary systems are common throughout the Milky Way Galaxy, increasing the statistical probability that life could arise elsewhere.13