On this day in 1969, Neil Armstrong became the first person to step on the Moon’s near-black, powdery surface as an estimated 600 million people back on Earth watched the historic moment live on television. The journey was an astounding technological achievement. But the scientific results and specimens from Armstrong and fellow crew member Edwin “Buzz” Aldrin’s 21-hour-and-36-minute stay on the lunar surface produced invaluable data and fueled research long after the mission was over. Instruments deployed during their moonwalk allowed for a precise measurement of the distance between Earth and Moon, analysis of the chemical composition of solar wind, and much more. The team gathered 22 kg of soil, dust, and rock samples—one of which was temporarily displayed at the Museum starting in November 1969, drawing record numbers of visitors at the time.