Welcome back to our ongoing series, A Brief-ish History of SETI, where we examine the ideas and milestones that have come to define the Search for Extraterrestrial Intelligence (SETI). In Part I , we looked at the purpose and motivations for this field of study, some of the earliest experiments, and how they reflected a growing sense of curiosity about the cosmos and our place in it. In Part II , we examined the first SETI survey (Project Ozma) and its enduring legacy.

We also saw how the project's leader, Professor Frank Drake (the "father of SETI"), proposed the famous Drake Equation , which remains a foundational principle of the field.…