This stunning collage captures the stages of a total lunar eclipse, where the Moon gradually enters Earth’s shadow and transitions from a bright, silvery disk to a deep blood-red orb. Over the course of ninety minutes, the Moon traverses the umbra, the darkest part of Earth’s shadow, as sunlight refracted by Earth’s atmosphere scatters shorter wavelengths, allowing only the longer, redder wavelengths to illuminate the lunar surface.
A lesser-known detail is that during totality, the exact shade of red can vary depending on Earth’s atmospheric conditions. Volcanic eruptions or high concentrations of dust and aerosols can deepen the hue, resulting in a darker eclipse. The Moon’s apparent brightness during totality can also be quantified using the Danjon scale, a system that ranks the darkness of a lunar eclipse from 0 (very dark) to 4 (bright and coppery red). This sequence beautifully illustrates the intricate interplay between celestial mechanics and atmospheric physics that give rise to this awe-inspiring phenomenon.
This stunning collage captures the stages of a total lunar eclipse, where the Moon gradually enters Earth’s shadow and transitions from a bright, silvery disk to a deep blood-red orb. Over the course of ninety minutes, the Moon traverses the umbra, the darkest part of Earth’s shadow, as sunlight refracted by Earth’s atmosphere scatters shorter wavelengths, allowing only the longer, redder wavelengths to illuminate the lunar surface.
A lesser-known detail is that during totality, the exact shade of red can vary depending on Earth’s atmospheric conditions. Volcanic eruptions or high concentrations of dust and aerosols can deepen the hue, resulting in a darker eclipse. The Moon’s apparent brightness during totality can also be quantified using the Danjon scale, a system that ranks the darkness of a lunar eclipse from 0 (very dark) to 4 (bright and coppery red). This sequence beautifully illustrates the intricate interplay between celestial mechanics and atmospheric physics that give rise to this awe-inspiring phenomenon.