Astronomical measurements 1923-2023: a century of astonishing progress

How have advances in technology changed astronomy over the past 100 years? In this very brief review I will give examples of just how closely discovery has followed technical innovation, allowing observations that would previously have seemed impossible. Obviously great progress has come from spaceflight allowing observations from outside the Earth's atmosphere. But two other factors have also been crucial-the development of efficient detectors of electromagnetic radiation and the application of computers to both instrument control and data analysis. Driving down experimental errors in pursuit of ever-more accurate measurements has been important too. I will particularly highlight advances in cosmology, the nature of galactic nuclei and the discovery of exoplanets.