Loved by audiences across Canada for making complex scientific issues understandable, meaningful, and fun, Bob McDonald is in high demand. A fixture in broadcasting for more than 30 years, he is currently the host of CBC Radio’s Quirks & Quarks–the award-winning science program that is heard by 500,000 people each week–and is the author of numerous bestselling books. In this recent blog for CBC.ca, Bob explains how vast distances and the problem of time make finding or contacting life beyond Earth very difficult.