On September 7, 2025, skywatchers throughout most of the Eastern Hemisphere may have noticed the full moon temporarily turning an orange-red color. Known as a "Blood Moon," the phenomenon occurs during a total lunar eclipse, when the Sun, Earth, and Moon align.
Astronauts aboard the International Space Station also witnessed the event. A crew member took this photograph of the Moon during the partial phase of the eclipse while orbiting over Central Asia. Most of the Moon's face was in Earth's shadow and appeared a coppery red. The total eclipse would begin about 5 minutes after this photo was taken, bathing the Moon fully in a reddish light.
A Blood Moon appears red because, during an eclipse, some sunlight still reaches the Moon's surface after interacting with Earth's atmosphere. Longer wavelengths of light -- reds and oranges -- pass through the atmosphere, while shorter-wavelength blues and violets are scattered. (The same effect turns the sky pink, orange, and red at sunrise and sunset.) The presence of clouds or dust in Earth's atmosphere can make the Moon appear redder during an eclipse.
The total phase of the September 7 eclipse lasted one hour and 22 minutes, the longest duration since the eclipse on November 8, 2022. The Blood Moon, if not obscured by clouds, would have been visible to people in Europe, Africa, Asia, and Australia -- an estimated 85 percent of the planet's population. The next total lunar eclipse will occur on March 3, 2026, and will be visible from the Americas, East Asia, Australia, and the Pacific.