In the journal Nature, NASA scientists suggest creating a scale that would allow different sources of data to be evaluated and combined to answer the perennial question of whether extraterrestrial life exists.
They envision a scaling pattern based on decades of experience in the field of astrobiology, which studies the roots of life on Earth and the potential for life elsewhere.
In the future, they wish that scientists would mention in their published studies how their emerging astrobiology results fall within such a scale.
The journalists might also reference this framework to clarify public expectations in articles about new scientific developments. This would ensure that minor steps do not appear as major leaps.
The framework has seven levels, which mirror the complicated, winding staircase leading up to scientists declaring they have found life beyond Earth.
Jim Green, the agency’s chief scientist, and his colleagues refer to the Technology Readiness Scale, a system used by NASA to assess how ready a spacecraft or technology is to fly. Under this scale, state-of-the-art technologies, including the Mars Ingenuity helicopter, initially start as only ideas and then turn into rigorously time-tested elements of historic space missions.
Mary Voytek, head of NASA’s Astrobiology Program and study co-author, explained, “Until now, we have set the public up to think there are only two options: it’s life, or it’s not life. We need a better way to share the excitement of our discoveries and demonstrate how each discovery builds on the next so that we can bring the public and other scientists along on the journey.”