From Orange to White: Satellites Record the Global LED Makeover of City Nightscapes

Astronaut Don Pettit’s ISS photos document a global shift from warm orange sodium-vapor streetlights to brighter white LEDs over the past 15 years, driven by cost and controllability. The transition changes how cities look and feel at night, with many places warming LED colors to ~3,000K after initial ~4,000K deployments; Hong Kong remains sodium-lit while nearby Shenzhen has switched to LEDs, illustrating the uneven adoption of the change.