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The Transit of Venus, Emebedded Devices,and Citizen Scientists

Embedded devices enabled citizen scientists to collect data during the Transit of Venus last week via cell phone and amateur radio.  By clicking a button on a phone app from at key times during the transit of Venus across the sun, users around the world collected time and position data that, when aggregated and published on the internet, will enable them to calculate the distance from Earth to the sun.  To accomplish the same thing in the 1700′s, Captain Cook mounted an expedition to Tahiti to collect data.

Ham radio operators collected transit data using the APRS network.  APRS stands for Automatic Packet Reporting System.  The system was originally developed by Bob Bruninga, for the United States Navy.  It’s a low speed wireless digital packet system that allows amateur radio operators to record data, such as their position, and send brief messages.  The packets are ultimately available via the internet.  In addition to collecting data of scientific interest, amateur radio operators also frequently track the positions of their cars and airplanes when they are out and about.  You can click on the picture below to fly over the Utah Salt Flats along the flightpath, (recreated vai APRS position packets and Google Earth), of airplane N175PT.

Utah Salt Flats via APRS

Utah Salt Flats via APRS

Forest Mimms III

Last week’s transit event wasn’t the first use of embedded devices and the internet to deploy geographically diverse collections of citizens for the advancement of science.  In the early 1990′s Forest Mims III, who many remember as the author of the Radio Shack Engineer’s Notebook series, designed a microcontroller enabled device that was used by students around the world to make ground based ozone measurements.  The invention earned him a Rolex Award for Enterprise.  The device was used by another group of students organized by Global Learning and Observations to Benefit the Environment, (GLOBE), to perform world-wide haze measurements.

Finally, a note of local interest.  While doing research for this article, I came across beautiful solar images of the transit, (one is shown at the start of the article), that were captured by NASA’s satellite-born Solar Dynamics Observatory.  It turns out that the data is beamed back to Earth to an antenna at the White Sands Missile Range just on the other side of the mountains east of town.

Moon over the Organs Photo - Hamilton Carter


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