Collecting a Time Capsule of Light with a Solarcan

This article was written by Brian Bartel ‘97

The Solarcan is a simple pinhole camera designed to capture the path of the sun daily over an extended period of time. There's nothing digital in this setup - light sensitive paper is the only thing inside the can. I installed this Solarcan on the Summer Solstice in June, facing south overlooking the solar array in Björklunden. Waiting almost six months, I removed and processed the image on December 14, 2024 - just before the Winter Solstice. The resulting image is called Solargraph, where each line represents the sun as it makes its path daily over six months from Solstice to Solstice. The highest band (not even fully visible in the picture) would be from the Summer Solstice, and the lowest band is close to the Winter Solstice (December 14). Days without lines (or broken lines) represent cloudy or rainy days where the sun isn't strong enough to be captured on the paper.

After retrieving this Solarcan, I installed three more on Björklunden grounds right before the Winter Solstice. It's ideal to install them in the winter as there aren't many leaves to block out the sun. In the last two years, I have also installed a few Solarcans at Lawrence University, on the roofs of Youngchild Hall, the Chapel and Music-Drama. You can see some of the results here.     

Björklunden Chapel Solarcan Puck Image

This has become a science hobby of mine over the last few years. Every time I open a Solarcan, I'm moved at the results showing the subtle changes that the earth and sun make over the course of time. Really, these images are just time capsules of light. But in my opinion, they also showcase science in art. This is the sentiment that I hope to instill with students in Appleton over the next year. With a grant from the Stan and Phyllis Thatcher Family Fund for STEM and the Diane Catlin Lang STEM Innovators and Girls Leadership Fund within the Appleton Education Foundation, I'll be working with 5th grade students to capture daily Solargraphs using a Solarcan Puck. Pucks use the same technology as the full Solarcan, but are designed for daily use and are reusable - perfect for younger students. You can see some of these "Puck" Solargraphs that I developed at Bjorklunden in the summer.

Björklunden Lodge Solarcan Puck Image