THIS DAY IN HISTORY: Astronauts in Quarantine.

On this day in 1969, multiple parades are held in honor of the Apollo 11 astronauts. They’d just been released from quarantine. Many people remember Neil Armstrong’s historic first step on the moon. But how many remember the quarantine that followed?

The entire crew was isolated for almost three weeks after they’d returned from that historic trip.

After all, no one knew for sure what the astronauts would bring home from the moon. What if they were exposed to a deadly lunar pathogen? Everyone needed to be sure that the astronauts were healthy before they came into contact with the general public again.

In addition to concerns about possible side effects from a moon landing, an ongoing news story that year may have also strengthened the desire for a lengthy quarantine: Woodstock Occurred in the Middle of a Flu Pandemic.