Science: Unlocking Potential

News and chat from the frontline of science and technology at PACA

This week, Quinty (the science tech) went down to the harbour early to bring back various fish and fish heads for the pupils to dissect. The aim of the project was to remove the lens from the fish eyeball. The job of the lens is to bend light in order to magnify the image of what the fish is looking at onto the retina at the back of the eye. The fish eye lens is perfectly round like a pearl bead, not convex in shape like ours. The special structure of the lens means that the fish eye can see things in very sharp focus.

The pupils thoroughly enjoyed the activity and I’m hoping that we can do more in the way of marine STEM education, considering our proximity to the sea. We then moved onto astronomy. The link might not seem immediately obvious but there is one: lenses and telescopes.
A refracting telescope uses lenses to form an image. In astronomical refractors, both the large objective lens and the eyepiece lens are convex. The objective lens focuses light from a distant object, forming an inverted image. The eyepiece lens then magnifies the image. Astronomers see the images upside down, but the orientation doesn’t matter to them.

“I’m hoping we can do more marine education, considering our proximity to the sea”

Sir Isaac Newton went on to develop the reflecting telescope. He replaced the convex glass lens in the refracting telescope with a curved mirror which reflected and focused the light (ref: Corning Museum of Glass). In doing so he overcame the problem of chromatic aberration, where images were surrounded by a colourful halo due to light passing through the glass lens. Going back to fishes though, this is another favourite quote of mine from Einstein: “Everybody is a genius. But if you judge a fish by its ability to climb a tree, it will live its whole life believing that it is stupid.”