The Apollo 11 mission was, in most respects, a feat of extraordinary precision.
Traveling at a maximum velocity of about seven miles a second, the Saturn V rocket would have launched the crew far off course in the event of even a slight navigational error. From nearly 240,000 miles away, Houston’s Mission Control could track the spacecraft’s position to within 30 feet. The command module’s guidance computer kept time to the millisecond.
And yet for all that precision, no one can say with absolute certainty when, exactly, Neil Armstrong first set foot on the moon.