Galileo’s closest approach to our planet in December 1990 allowed scientists to perform the first controlled experiment for the search for life on Earth from space. Ten months earlier, Voyager 1 had returned the iconic ‘Pale Blue Dot’ image. From beyond the orbit of Neptune, Earth appeared as a mere fraction of a pixel. The planetary portrait was captured at the suggestion of Carl Sagan, who was also the designer of the Galileo flyby experiment. The Pale Blue Dot became an instant symbol for a civilization stepping out of its planetary cradle in search of life beyond Earth. Success would require that humanity redefine itself from a cosmic perspective. Within 10 months of the Pale Blue Dot delivering the philosophical message, the Galileo experiment provided a scientific roadmap for the journey.

In a commentary commissioned by Nature Astronomy for the 100th Anniversary of the IAU and published on July 5th, 2019, Dr. Nathalie A. Cabrol, astrobiologist and Director of the SETI Institute Carl Sagan Center for Research shows how, 26 years after its publication, A search for life on Earth from the Galileo spacecraft by Sagan et al. (1993) reveals a fused vision of a future of biosignature detection in the Solar System and beyond that is even more relevant today.

You can read the full article at:
https://www.nature.com/articles/s41550-019-0839-3.epdf?author_access_token=WXdpWIIvGJeTn1khGF67RdRgN0jAjWel9jnR3ZoTv0M2090hjzd3iAY8Y_7pOmkQ5jAuZcceUL2M1XuY4rFPJyt9-TBcnJZ6XSIJC-WNDLxBjEGkpL8QTL3WuqNPMnZX3qjmxGEUwidwNtPSm9-6bQ%3D%3D