Lightman was born in Memphis, Tennessee, in 1948, the son of Richard Lightman, a movie theater owner, and Jeanne Garretson, a dancing teacher and volunteer Braille typist. From an early age, he was entranced by both science and the arts and, while in high school, began independent science projects and writing poetry. He won state-wide science fairs and was the state winner of the National Council of Teachers of English literary award.
In 1966, he graduated from White Station High School in Memphis. Lightman received his AB degree in physics from Princeton University in 1970, Phi Beta Kappa and Magna Cum Laude, and his Ph.D. in theoretical physics from the California Institute of Technology in 1974. He has received five honorary degrees. From 1974 to 1976, Lightman was a postdoctoral fellow in astrophysics at Cornell.
During this period, he began publishing poetry in small literary magazines. He was an assistant professor of astronomy at Harvard from 1976 to 1979 and, from 1979 to 1989, a research scientist at the Harvard-Smithsonian Center for Astrophysics. In 1981, Lightman began publishing essays about science, the human side of science, and the “mind of science,” beginning with Smithsonian Magazine and moving to Science 82, The New Yorker, and other magazines.
Since that time, Lightman’s essays, short fiction, and reviews have appeared in The American Scholar, The Atlantic Monthly, Boston Review, Daedalus, Discover, Exploratorium, Granta, Harper’s, Harvard Magazine, Inc Technology, Nature, The New Yorker, The New York Review of Books, The New York Times, Science 86, The Sciences, Smithsonian, Story, Technology Review, and World Monitor.