Free Astronomy Magazine May-June 2018

38 ASTROBIOLOGY The Silurian Hypothesis − Something to think about by Michele Ferrara revised by Damian G. Allis NASA Solar System Ambassador MAY-JUNE 2018 T he Earth re-flourished after the catas- trophe that extinguished the dinosaurs. In this age and in the millions of years that followed, an ancient industrial civilization could have developed. [Donna Braginetz, Denver Museum of Nature and Science]