Walking through the Phoenix airport last week, I was struck by one of the many large video screens overhead. Phoenix will be hosting the NCAA Men’s Basketball Final Four this year, and the screen showed how many days, hours and minutes (no seconds) until tipoff of the first semifinal game.

Counting down to a big event is hardly new. A little more than three months before I was born, my parents most likely watched the Times Square crowd shouting out the final 10 seconds of 1953.

More analoggy, advent calendars were a form of counting down the final 24 days until Christmas.

But countdown clocks, the 00:00:00 format that has become ubiquitous, really came into vogue in the early 1960s with the telecasts of the first manned space missions, Project Mercury.

A clock on the screen would show the minutes and seconds until the scheduled launch. When the clock was ticking down the numbers, there was nervous anticipation. 

And then, just as you were thinking you’d be seeing a launch, the clock would stop. That happened often in the early days, especially in the leadup to John Glenn’s first U.S. orbital flight.

Then the voice of the NASA, Shorty Powers, would explain what was going on. The hold was at T-minus 6:00 because of some warning light.

Those countdown clocks survived the early space buzz. There are digital countdown clocks everywhere. TV news networks use them to hype big events. Chambers of commerce love to count the days:hours:minutes;seconds to some festival or sporting event.

And people who write things love to use the countdown to tick off the days until, say, their 70th birthday.