14-Year-Old Boy May Have Captured First Photo of Shadow Cast by Jupiter

While most 14-year-old boys are hooked on things like video games, Laurent V. Joli-Coeur is busy using astronomy and photography for crazy science projects. A few months ago, he had the crazy idea of photographing a shadow caused by Jupiter’s light. He then spent 7 hours building an instrument to do so, and used a Nikon D700 and 60mm Macro lens lent to him by Nikon to capture the image:

I took three photographs to prove that Jupiter could indeed cast a shadow. The first one, a five minute exposure at ISO1600 with an in-camera dark subtraction, was taken to photograph a shadow: the results were conclusive. Indeed, after stretching the image in Pixinsight, the gnomon’s shadow was clearly visible on the projection screen (a gnomon is the object that creates the shadow on a sundial). However, this wasn’t enough to prove it was Jupiter’s. The second exposure was taken to prove that the light causing the shadow came from the sky, not from the instrument itself: I slightly moved the mount in right ascension, expecting the shadow to move sideways… And it did. The third and final exposure was taken in a region of the sky far away from Jupiter. As the last image showed no sign of the gnomon’s shadow, I concluded that the only possible explanation for the shadow in the first two images was Jupiter!

As far as Joli-Coeur knows, it’s the first photo of a shadow cast by Jupiter ever made. You can find a more detailed account of his experiment on his blog.

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