On the night of March 13, 2025, or early morning of March 14, depending on time zone, the Moon will pass into Earth's shadow and appear to turn red. This celestial event, known as a total lunar eclipse, will be visible from Earth's Western Hemisphere.
A lunar eclipse occurs when the Sun, Earth, and Moon align, causing the Moon to pass into Earth's shadow. During a total lunar eclipse, the entire Moon falls within the darkest part of Earth's shadow, called the umbra. This results in the Moon taking on a reddish-orange hue, a phenomenon that has earned lunar eclipses the nickname "Blood Moons."
To observe this celestial spectacle, no special equipment is required, although binoculars or a telescope can enhance the view. For optimal viewing conditions, seek a dark environment away from bright lights.
The reddish-orange color of the Moon during a lunar eclipse is caused by the same phenomenon that makes our sky blue and our sunsets red. Sunlight, while appearing white, is actually composed of a rainbow of colors, each with distinct physical properties. Blue light scatters easily as it passes through Earth's atmosphere, while reddish light travels more directly.
When the Sun is high in the sky on a clear day, we observe scattered blue light throughout the sky. However, at sunrise and sunset, when the Sun is near the horizon, incoming sunlight travels a longer, low-angle path through Earth's atmosphere. This causes the bluer portion of the sunlight to scatter away in the distance, leaving only the yellow-to-red portion to reach our eyes.
During a lunar eclipse, any sunlight not blocked by Earth is filtered through a thick layer of Earth's atmosphere before reaching the lunar surface. This filtering process results in the Moon appearing red or orange, as if all the world's sunrises and sunsets are projected onto its surface.
On the night of the eclipse, look towards the western sky for a glimpse of planets Jupiter and Mars. At the eclipse's beginning, the Moon will be in the constellation Leo, under the lion's hind paw. Shortly after, it will move into the constellation Virgo. As Earth's shadow dims the Moon's glow, constellations may become more visible than usual.