Extraterrestrial

Space missions could be missing signs of alien life, scientists warn

By T.K. Randall
May 21, 2026 ·  14 comments

Image Credit: Courtesy NASA/JPL-Caltech Most people will be familiar with the term 'false positive' with regard to the search for alien life, which is when a result - such as an analysis of a soil sample on Mars - shows the presence of extraterrestrial organisms when in actual fact there are none.

A famous example of this was when NASA's Viking 1 lander seemed to have detected signs of life on Mars - a result that is today generally believed to have been a false positive.

But what if the opposite could also happen - a 'false negative' as it were ?

In other words, what if Mars rovers and landers have been sitting right on top of concrete evidence of alien life for decades but every test has still come back negative ?"We should be aware of these false-negative results," said astrobiologist Inge Loes ten Kate, lead author of a study investigating the consequences of such a scenario.

"It means there are shortcomings in recognizing the existence of life."

"These shortcomings are not yet high on the research agenda."

Ten Kate, and colleagues, are now advocating for new research strategies designed to assess the risks of potential false negatives and how to address them.

"The search for signs of life should go hand in hand with better-defined questions and testable hypotheses to justify specific measurement or observation targets," she said.

Source: Phys.org | Comments (14)

Tags: Alien, Extraterrestrial