Advocating for Planetary Protection and Global Responsibility

Sagan was not only a scientist but also a moral voice on the dangers facing humanity. His research on the greenhouse effect on Venus was an early warning about climate change on Earth. He co-authored pioneering studies on nuclear winter, showing how a large-scale nuclear war could trigger catastrophic global cooling and collapse ecosystems. Beyond warnings, Sagan was a vocal advocate for planetary protection—arguing that as we explore space, we must avoid contaminating other worlds and also protect our own. His famous reflection on the Pale Blue Dot photograph captured by Voyager 1 summarized this ethic perfectly: that all of human history, every person and every story, has unfolded on this “tiny mote of dust suspended in a sunbeam,” and therefore it is our duty to cherish and preserve it.