He had prepared for this space mission for years, starting as a boy fascinated by the Apollo program and continuing through rigorous astronaut training.
Still, as Bernard A. Harris Jr. stepped out of the space shuttle Discovery in 1995—the first African-American to walk in space—he hesitated, afraid he might get sucked out of the craft’s air lock and fall 250 miles to Earth.
Holy cow, Harris thought as the Earth flew by far below at 17,500 miles per hour.
“I am really doing this,” Harris recalled thinking. “It was just incredible.”