While we understand that the Earth rotates to produce day and night, and tilts on its axis to vary the day’s length, how is the planet positioned in relation to the sun right now? Unless you’re well-attuned to our solar system’s rotational dance, this is difficult to visualize. To help with this, hacker “SimonRob” came up with a clock that shows how the sun shines in real-time at all points on the Earth.
An array of LEDs provides artificial lighting for the device, which rotates a nicely painted physical globe around a daily axis, along with a much larger rotational axis that controls the Earth’s tilt. Both are controlled via stepper motors, which are in turn controlled by an Arduino Uno and a bevy of supporting electronics.
It’s a clever concept, and a well-executed build, so be sure to check out the project write-up for more information!