Without land, rain would not weather rock and release important nutrients like phosphorus. Photosynthetic life could not produce oxygen at rates comparable to other nonbiological sources.

“The detectability index tells us it’s not enough to observe oxygen in an exoplanet’s atmosphere. We must also observe oceans and land,” Desch said. “That changes how we approach the search for life on exoplanets. It helps us interpret observations we’ve made of exoplanets. It helps us pick the best target exoplanets to look for life on. And it helps us design the next generation of space telescopes so that we get all the information we need to make a positive identification of life.”

Scientists from diverse fields were brought together to create this index. The formation of the team was facilitated by NASA’s Nexus for Exoplanetary System Science (NExSS) program, which funds interdisciplinary research to develop strategies for looking for life on exoplanets. Their disciplines include theoretical and observational astrophysics, geophysics, geochemistry, astrobiology, oceanography and ecology.

“This kind of research needs diverse teams, we can’t do it as individual scientists” said co-author Hilairy Hartnett, who holds joint appointments at ASU’s School of Earth and Space Exploration and School of Molecular Sciences.

In addition to lead author Glaser and co-authors Harnett and Desch, the team includes co-authors Cayman Unterborn, Ariel Anbar, Steffen Buessecker, Theresa Fisher, Steven Glaser, Susanne Neuer, Camerian Millsaps, Joseph O’Rourke, Sara Imari Walker and Mikhail Zolotov, who collectively represent ASU’s School of Molecular Sciences, School of Earth and Space Exploration, and School of Life Sciences. Additional scientists on the team include researchers from the University of California Riverside, Johns Hopkins University and the University of Porto (Portugal).  

It is the hope of this team that this detectability index framework will be employed in the search for life.

“The detection of life on a planet outside our solar system would change our entire understanding of our place in the universe,” Glaser said. “NASA is deeply invested in searching for life, and it is our hope that this work will be used to maximize the chance of detecting life when we look for it.”

Karin Valentine

Media Relations & Marketing manager, School of Earth and Space Exploration

480-965-9345