This incredible close-up image, taken using a scanning electron microscope (SEM), shows a polymer microparticle around 300 microns in diameter. Such microparticles are being developed with the aim of attaching them to the end of an optical fibre and using them to ‘sense’ the surrounding pH (or acidity) of the lung, using a technique called Surface Enhanced Raman Spectroscopy (SERS). Measuring the pH of the fluid within tiny gas-exchanging air sacs (alveoli) can give scientists an idea of cell function, antibiotic action, and an indicator about the overall lung health.
Interestingly, not only does the microparticle bear a striking resemblance to an astronomical body, but its similtude also crosses over into the realm of science fiction. Mimas, a tiny moon of Saturn shown on the right hand side of the image below, displays an impressive 130km-wide impact crater named after its discoverer, William Herschel. The image on the left hand side is one that has become deeply ingrained in Western popular culture – the famous Death Star from George Lucas’ Star Wars film franchise. This ultimate weapon of the evil Empire is capable of destroying an entire planet using its superlaser that emanates and converges from a giant 36 km-wide aperture.