I was born in Berea, Kentucky and graduated from Berea College with a degree in Geology. I hold a Ph.D. in Geochemistry from the Massachusetts Institute of Technology and several honorary degrees, including Doctor of Science degrees from Berea College and from Oberlin College. I taught Geology at Oberlin College for over 20 years. I have long been a Fellow of the Geological Society of America.

I served as Acting President of Oberlin, President of Franklin and Marshall College, President of Reed College, President of the Franklin Institute Science Museum in Philadelphia, and President and Director of the Los Angeles County Museum of Natural History. President Ronald Reagan and later, President George H. W. Bush, appointed me to the National Science Board, where I served for 12 years. Asteroid 9739 Powell is named for me. In January 2022 I retired after 20 years as the Executive Director of Graduate Fellowships for STEM Diversity.

The most recent of my books is Mysteries of the Deep: How Seafloor Drilling Expeditions Revolutionized our Understanding of Earth History, from MIT press. Other recent titles are Unlocking the Moon's Secrets: From Galileo to Giant Impact, published by Oxford University Press in 2023, The 2084 Report: An Oral History of the Great Warming, and Deadly Voyager: The Ancient Comet Strike That Changed Earth and Human History. Faith in Fallacy: A Century of State-Sanctioned Science Denial, will appear in late summer 2024.

Two honors of which I am most proud is that, first, my former student and friend, the late Rick Black, and his wife Robin donated funds to build a new geology laboratory named for me at Oberlin College. As I said at the dedication, to be recognized for teaching at a school that exemplifies excellence in teaching is as good as it gets. Second, Berea College recognized me as one of 100 "Notable Bereans" with a banner on campus. I have been most fortunate to have been associated with these two "colleges of character." They have given me a lot to live up to.