News - NASA assumes presence of chemical signs of life on 17 exoplanets

In a new analysis, NASA has revealed that 17 discovered exoplanets could house subsurface oceans buried below thick sheets of ice, Space.com reported.  These worlds, much like the icy moons of Jupiter, could therefore be promising places to search for biosignatures—chemical signs of life. The research was published in The Astrophysical Journal. While the exact composition of these worlds remains unclear, estimates of their surface temperatures from previous studies point them being significantly colder than Earth. They're also each less dense than Earth, despite being roughly the same size as our planet. "Our analyses predict that these 17 worlds may have ice-covered surfaces but receive enough internal heating from the decay of radioactive elements and tidal forces from their host stars to maintain internal oceans," Lynnae Quick of NASA's Goddard Space Flight Center said in a statement. In other words, while their host stars may not provide conditions warm enough to keep water in liquid form on their surfaces, these planets may exhibit processes that can generate heat below their surface.