Sun Set Clock

Technology separates us from nature, but does it need to? I used some of my stay at the Digital Naturalism Conference in Thailand to prototype a clock that determines local time of day from sunlight to promote a natural sense of timekeeping.

By using technology to encourage human relationships with nature, I hope to highlight that machines can encourage us to be *more* human and organic rather than slowly making people irrelevant. As a counterpoint to consuming industrialized time we can also obtain time from scratch, regaining control of the very pacing that drives our lives. The Sun Set Clock uses local solar time, therefore noon is when the sun is at apogee at our location. This is how time used to be measured, before telegraphs and transcontinental trains required a move to time zones, where the clock and the sun no longer match. This system isn’t concerned with exactitude–there’s plenty of systems to do that if you need it. Instead this clock can be used to mark the general progress of the day rather than creating anxiety around how every minute is used.

Sun Set Clock in its natural environment

The initial prototype uses light level changes to detect sunrise and sunset, with local noon being the point exactly between these two events. When the clock starts, it makes its best estimate of the time. For example, if it’s dark at startup, the clock assumes that it’s midnight because that’s the best guess you can make without more information. At sunrise, this corrects to 6 am (a higher-quality guess) and then at sunset it will correct to the proper local time (not time zone time but astronomical time at your precise location). All of this works, although it’s still a bit fragile–operating best in full view of the sky on a relatively sunny day. Dark clouds, deep shadows and porch lights can confuse it, so these will need to be addressed in a future version. For now, I’m enjoying what I think of as “some time of my own.” I hope you enjoy it too.


Sun Set Clock – Instructions for Use
system diagram

Sun Set Clock, using BBC micro:bit and Grove light sensor

PARTS LIST

Koh Lon in Thailand: a nice place to make a clock
Light sensing graph–Koh Lon Island
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