A lunar eclipse occurs when the Earth moves directly between the sun and the moon.
In this case, the Earth blocks light from the sun and casts a shadow on the moon's surface, dimming it and causing it to turn red for a few hours.
The Earth’s shadow in a lunar eclipse involves two parts, namely the umbra and the penumbra.
The umbra is the darkest part and the inner part of the shadow, whereas the penumbra is the brightest and outermost part of the shadow.
According to NASA, the moon obtains its red color based on the position it lies on the Earth’s shadow, in this scenario, the umbra.
Due to the bending of light, the colors with the shortest wavelengths, such as the blues and violets, are scattered easily, whereas the colors with the longest wavelengths, the red and orange, make it to the moon’s surface.
Because of this, the moon will appear reddish or orangish during the lunar eclipse. The more dust or clouds in Earth’s atmosphere during the eclipse, the redder the Moon appears.
"The same phenomenon that makes the sky blue and our sunsets red causes the Moon to turn reddish-orange during a lunar eclipse. Sunlight appears white, but it actually contains a rainbow of components—and different colors of light have different physical properties. Blue light scatters relatively easily as it passes through Earth’s atmosphere. Reddish light, on the other hand, travels more directly through the air," NASA says.
This March, we are likely to experience a total lunar eclipse, with the moon falling into the darkest part of the Earth’s shadow.
The eclipse is expected to happen (today) March 13 and March 14 for about six hours at night, offering skywatchers a lovely view as the moon moves through the Earth’s shadow.
According to Exploratorium, the Earth experiences an average of three lunar eclipses every year.
Each lunar eclipse is visible from half of the Earth or anywhere the moon is above the horizon.
Furthermore, exploratorium says that it is safe to observe the eclipse without any special eyewear or glasses.
They further explain the relative positions, stating that if you were standing on the moon, Earth would block your view of the Sun during a lunar eclipse.
