NASA astronaut shows how the switch to LED lighting changed Earth's cities as seen from orbit

NASA astronaut Don Pettit shared a series of photos showing how cities around the world have changed in recent years after switching from sodium lamps to LED lighting.

Across 23 years and four missions to the ISS, Pettit has photographed major cities on Earth, building his own archive of changes in nighttime lighting. The familiar yellow-orange glow of gas discharge lamps is increasingly giving way to multi-colored LED systems, installed partly for energy savings.

The change is especially noticeable in Miami. In the 2025 photo, the city grid looks significantly brighter and more colorful than during Pettit previous mission.

The switch to LEDs has noticeably changed how cities look from orbit.