Two factors dominate our search for life and habitability elsewhere in the galaxy. The first is liquid water, which, as far as we know, is necessary for life. When we find exoplanets, scientists try to determine if they're in their stars' habitable zones. Under the right atmospheric conditions, liquid water could persist there. The second is biosignatures. One of the reasons the JWST was built was to study exoplanet atmospheres and determine their contents, and it's found some very interesting potential biosignatures. But scientists struggle with the fact that an atmospheric biosignature here on Earth could have a non-biological origin on exoplanets that are much different from Earth. One of the ways forward is to develop an agnostic viewpoint. That's the focus of new research in The Astrophysical Journal titled "An Agnostic Biosignature Based on Modeling Panspermia and Terraforming." The authors are Harrison Smith from the Earth-Life Science Institute (ELSI) at Institute of Science Tokyo and Lana Sinapayen from the National Institute for Basic Biology in Okazaki City, Japan. "Realistically, there are just a few locations to search for alien life within the solar system," the authors write. "Outside the solar system, opportunities are nearly unlimited, but thereâs a catch: it is difficult to attribute, with certainty, features of exoplanets to extraterrestrial life." The authors point out that individual biosignatures are susceptible to false positives, and that searching for technosignatures isn't much better. They're based on a whole host of underlying assumptions about the nature of a civilization's technology and culture. This work is focused not on individual exoplanets, biosignatures, and technosignatures, but on situations where life is spreading from world to world. "We have developed an agnostic approach to exoplanet life detection that overcomes these limitations by using properties that emerge on the scale of groups of planets, without