An Observational Signature of Evolved Oceans on Extrasolar Terrestrial Planets

http://www.iop.org/EJ/article/1538-4357/605/1/L65/18164.text.html

The possible existence of life on other planets is of central interest in modern astronomy. A standard working hypothesis is that liquid water is required for life; here we describe an observational signature of evolved oceans on extrasolar terrestrial planets.