It looks like it’s zero hour for the NASA countdown clock. After more than 40 years of operation at the Kennedy Space Center – the clock is set to be replaced by a more modern LED display.
It’s interesting to use the retirement of the clock as a data point on how fast display technologies are now changing. Although most of the world moved to LED displays over a decade ago – the iconic countdown clock, when it was originally envisioned, was a pretty interesting display. The clock is made up of about 350 “pixels” of resolution. Each of these pixels was a 40-watt lightbulb that was controlled through a set of analog circuits to illuminate each on demand, creating a digital clock display. Although the display was a workhorse for more than 4 decades – after all, how long will your latest LED television last? – its specs, by modern standards are miserable. The display contains about 48 pixels in a horizontal row, spread over about 20 feet. That translates to a pixel density of about 0.2 pixels-per-inch (or “dot pitch” for the AV geeks like me out there). Even the most lowly LED advertising sign gracing the side of the highway may have a dot pitch of 12mm, or one pixel every .47 inches. This corresponds to a DPI of 2.12.
Brightness and power efficiency are, of course, getting a major upgrade as well. Typical incandescent bulbs produce about 11 lumens of brightness per watt. So those old 40-watt bulbs were generating about 450 lumens. Compare this to an average LED that can generate 160 lumens/watt. It makes you wonder what took NASA so long…nostalgia perhaps. But they have said the new display will cost around $280,000. Congrats to the AV company installing to the new display – that’s a lot of light bulbs.