Posts with «sun» label

Watch The World Spin With The Earth Clock

With the June solstice right around the corner, it’s a perfect time to witness first hand the effects of Earth’s axial tilt on the day’s length above and beyond 60 degrees latitude. But if you can’t make it there, or otherwise prefer a more regular, less deprived sleep pattern, you can always resort to simulations to demonstrate the phenomenon. [SimonRob] for example built a clock with a real time rotating model of Earth to visualize its exposure to the sun over the year.

The daily rotating cycle, as well as Earth’s rotation within one year, are simulated with a hand painted plastic ball attached to a rotating axis and mounted on a rotating plate. The hand painting was done with a neat trick; placing printed slivers of an atlas inside the transparent orb to serve as guides. Movement for both axes are driven by a pair of stepper motors and a ring of LEDs in the same diameter as the Earth model is used to represent the Sun. You can of course wait a whole year to observe it all in real time, or then make use of a set of buttons that lets you fast forward and reverse time.

Earth’s rotation, and especially countering it, is a regular concept in astrophotography, so it’s a nice change of perspective to use it to look onto Earth itself from the outside. And who knows, if [SimonRob] ever feels like extending his clock with an aurora borealis simulation, he might find inspiration in this northern lights tracking light show.

This is a spectacular showpiece and a great project you can do with common tools already in your workshop. Once you’ve mastered earth, put on your machinists hat and give the solar system a try.

Hack a Day 18 Jun 16:31

Tracking Solar Brightness with a Homemade Sun Logger

The Sun Logger, a data logging device, combines several components we’ve used in previous Weekend Projects. You may recognize the light-sensitive photoresistor (Optical Tremolo Box) and the Arduino Uno microcontroller (Touchless 3D Tracking Interface). These parts, when combined with a 74AHC125 Level Shifter and SD card socket mounted on a homemade “shield,” will record the levels of light shining down on your project box. That data, recorded every 15 seconds to the SD card, can be exported later to any popular spreadsheet software and graphed, giving you a visual representation of light changes over time. This data could aid in knowing where best to plant a garden, or simply to understand changes of light intensity throughout the seasons in your micro-climate.

And while this project is readymade for recording levels of sunlight, the Arduino has a total of six analog inputs (labeled A0 – A5) and could easily record other variables. For example temperature, motion, or barometric pressure. Makers looking for a mid-level Arduino build, or knowledgeable coders looking to solder together their first homemade shield, the Sun Logger is a great project to build!

Filed under: Arduino, MAKE Projects, Weekend Projects