ites, those alien rock fragments that have survived their fiery descents through our atmosphere to land here on Earth.

She is Head of Collections and Principal Curator of Meteorites at the Natural History Museum, home to one of the finest meteorite collections in the world. Her interest in rocks began while wandering the foothills of the Rocky Mountains, as a child, picking up the ones that caught her eye and bashing them with a hammer, hoping to find treasure inside, whether it’s gold, diamonds or dinosaur fossils.

Her work today, studying rocks that have landed here on Earth or those still out there in space, is no less ambitious. She analyses their chemical composition looking for tantalising clues that might reveal how our Solar System formed, and potentially the presence of the chemical building blocks necessary for life itself.

Presented by Jim Al-Khalili Produced by Beth Eastwood Executive Producer: Alexandra Feachem BBC Studios Production

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From humble beginnings in his native Sri Lanka, to a more than 40 year academic career at Queen’s University Belfast, Prof. AP (Amilra Prasanna) De Silva’s research into molecular photosensors has led to a pioneering career in that’s evolved from chemistry to medical diagnostics on one hand, to information processing on the other.

Prof. De Silva challenged cultural expectations and overcame the lack of opportunities in chemistry that were available in Sri Lanka in the early 1970s. He first moved to Belfast to pursue research in photochemistry at Queen’s University. Inspired by his grandmother’s struggle with high blood pressure he engineered a unique sodium photosensor by marrying fluorescent molecules with chemical receptors. As a result of his international collaborations, a commercial, portable sensor was developed to detect salts and minerals in the blood. Its speed of analysis has since saved countless lives and improved healthcare around the world.

AP talks to Jim Al-Khalili about his passion for engineering

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