Saturday, February 22, 2020 1:30 pm - 3:30 pm
David Helfand / Columbia University
When Galileo turned the first telescope to the Milky Way, he found it was composed of tens of thousands of stars. He called them other "Suns" and speculated about the life their encircling planets might harbor. For most of the last 400 years this rampant speculation is all we knew about life beyond Earth.
In the last two decades, however, our knowledge has expanded explosively. We've gone from knowing about the eight planets circling our Sun, to billions in the Milky Way. We uncovered vast clouds of organic molecules, the building blocks of life, in regions of space where new stars are forming. And we've found life flourishing in extreme environments on Earth. We are now in a position to provide a quantitative estimate of prospects for life beyond Earth, and even to calculate the number of intelligent civilizations in the Milky Way. This illustrated lecture will present the results of these discoveries, as well as exploring the important issue as to whether or not our species yet qualifies as intelligent life in the cosmic sense.
David Helfand has been a Professor of Astronomy at Columbia University for 42 years where he served as chair of the Department for nearly half that time. He is also the former President of the American Astronomical Society and of Quest University Canada, and currently serves as Chair of the American Institute of Physics. He has received the Columbia Presidential Teaching Award and the Great Teacher Award from the Society of Columbia Graduates. He is the author of the new book, “A Survival Guide to the Misinformation Age.”