The characteristic red-color change (referred to as a "Blood Moon") associated with a total lunar eclipse is the result of Earth’s atmosphere. NASA explains that during totality, the Earth blocks direct sunlight from reaching the lunar surface. However, the atmosphere filters the light, scattering shorter blue wavelengths and allowing longer red wavelengths to pass through and bend toward the Moon. This process, called "Rayleigh Scattering," is the same process that creates red sunrises. During a lunar eclipse, the scattering refracts or projects the light of all the world’s sunrises and sunsets at once onto the Moon, which the Moon then reflects back to us. Additionally, according to NASA, the intensity of the red can be influenced by local atmospheric conditions; for example, more dust or clouds in Earth's atmosphere can make the red appear even darker.

Timing

For community members and visitors in Cook County, the pre-dawn viewing window for the total lunar eclipse begins at 3:50 a.m. CST on Tuesday, March 3, 2026, when the Earth's shadow first touches the lunar surface. According to NASA, the point of totality will take place between 5:04 a.m. and 6:02 a.m. CST, during which the Moon will be positioned low in the western sky. The moon will set at 6:40 a.m., just minutes after totality ends and the sun rises. 

If the skies are cloudy or you miss this one, according to NASA’s schedule of future lunar events, the next total lunar eclipse visible from North America will not take place until June 2029. However, a partial lunar eclipse is expected to occur in August 2026.