For centuries, people have wondered if life exists beyond Earth. Astrobiology, the science of studying life in the universe, tries to answer some of the biggest questions of all: How did life begin?
Could it exist elsewhere? And if so, will we ever find it?
A new study published in PLOS One by researchers at Leiden University looked at how this search has been portrayed in public conversation from 1996 to 2024.
They examined three sources of information—scientific papers, press releases, and news articles—to understand how speculation and promises about extraterrestrial life appear in the media.
The team found that the most common speculations focused on the conditions needed for life, such as water, chemical ingredients, or a planet’s atmosphere.
Speculation about whether life actually exists elsewhere was also frequent.
What was less common were guesses about what the outcome of the search might be. Even rarer were claims of possible evidence of alien life.
Technology plays an important role in the way this search is described.
About one-third of news stories suggested that new instruments and telescopes might help us discover life, compared with one-fifth of press releases and only one-tenth of scientific papers.
Similarly, the promise that astrobiology is making progress toward finding life appeared often in news stories and press releases, but much less in academic studies.
What the researchers rarely saw were bold promises that life has been, or soon will be, detected. “In general, scientists don’t seem comfortable setting expectations about the prospects of life detection when talking about their own research,” said Danilo Albergaria, the study’s lead author.
News articles turned out to be the most speculative overall, containing more guesses and promises than either press releases or scientific papers.
However, press releases were more likely to speculate when describing the importance of a study, which may reflect the pressure institutions feel to make research sound impactful and grab media attention.
Interestingly, speculation in press releases was often placed directly in the mouths of researchers through quotes.
In news articles, speculation was more evenly split between quotes from scientists and statements without attribution. This highlights the influence researchers themselves have in shaping how the search for life is communicated.
The study also showed that hopes about finding life were more often linked to the study of exoplanets—planets orbiting other stars—than to research on our solar system or the ongoing Search for Extraterrestrial Intelligence (SETI).
Albergaria notes that speculation isn’t necessarily harmful. “Speculative imagination helps to develop concepts and hypotheses that guide the search,” he said. “There are many unknowns about life in the universe, which makes speculation in astrobiology almost inevitable.”
The study analyzed 630 articles published in English, Portuguese, and Spanish, including coverage in six major newspapers: The New York Times, The Guardian, Folha, Estadão, Público, and El País.
