Why do we reside on the 3rd of four rocky planets orbiting a G dwarf star which itself orbits the galactic centre once every 240 million years at a distance of some 27 light years? Did our ancestors originate here? How? Does (or did) life exist elsewhere in our solar system? If so, is (or was) it genetically related to us Earthlings? Could there be life beyond the solar system? For generations, these questions have inspired fanciful hypotheses and science fiction stories and will continue to do so for as long as literate Earthlings survive. But meanwhile, recent discoveries in the fields of astronomy, geology, and biology are revamping our understanding of our own planet’s history, how life may have started here (we’ll never know for sure), and the subsequent co-evolution of Earth and its inhabitants.
In this talk, I will first focus on what we have recently learned about the availability of pre-biotic building blocks for life, how their assembly into the first cells on Earth may have occurred, and what energy source(s) powered life to take hold and survive until today, emphasizing events in the first 2 billion years of the solar system’s history. New insights gained from continued local prospecting can serve to refine criteria when searching for signs of extraterrestrial life. Specifically, they suggest testable hypotheses about what we may find in current missions to our nearest neighbours, Venus and Mars, and could be used to sharpen strategies for future prospecting for life beyond the solar system.
Dorothy Paul is a biologist and amateur astronomer. Prior to retirement from the University of Victoria, her research was in neuroscience and evolutionary neurobiology. She now spends much of her time in pursuing and sharing her interests in biology and astronomy locally, at star parties and schools, and when possible, with her telescope under dark skies, hunting down distant objects in and beyond our Milky Way galaxy.