Cathal O’Connell is a researcher in 3D bio-printing with a background in physics and nanoscience. Now based at St Vincent’s Hospital in Melbourne, he works with surgeons, engineers and biologists to develop ways to 3D-print body parts. In 2014, he co-authored an e-book about the field, 3D Bioprinting: Printing Parts for Bodies (ARC Centre for Excellence). He is also a freelance science writer, specialising in physics and technology, and has contributed more than one hundred articles to Cosmos Magazine about about space, relativity and quantum mechanics.