The moon took on an eerie blood-red hue early Tuesday during the first total lunar eclipse of 2014, a celestial sight that wowed potentially millions of stargazers across North and South America.
The total lunar eclipse of April 15 lasted about 3.5 hours between late Monday and early Tuesday, with the Earth’s shadow slowing darkening the face of the so-called “Blood Moon” in a jaw-dropping sight for stargazers willing to stay up extra late or rise super-early for the event.
The lunar eclipse peaked at 3 a.m. ET, with the moon taking 78 minutes to pass through the darkest point of Earth’s shadow. It was visible from most of North and South America, Hawaii and parts of Alaska. The eclipse was the first of four consecutive total lunar eclipses, known as a “tetrad,” between April 2014 and September 2015.
A lunar eclipse occurs when the Moon passes directly behind the Earth into its umbra (shadow). This can occur only when the Sun, Earth, and Moon are aligned exactly, or very closely so, with the Earth in the middle. Hence, a lunar eclipse can only occur the night of a full moon. The type and length of an eclipse depend upon the Moon’s location relative to its orbital nodes.
Unlike a solar eclipse, which can only be viewed from a certain relatively small area of the world, a lunar eclipse may be viewed from anywhere on the night side of the Earth. A lunar eclipse lasts for a few hours, whereas a total solar eclipse lasts for only a few minutes at any given place, due to the smaller size of the moon’s shadow. Also unlike solar eclipses, lunar eclipses are safe to view without any eye protection or special precautions, as they are dimmer than the full moon.
During an eclipse, sunlight shining through the ring of Earth’s dusty atmosphere is bent, or refracted, toward the red part of the spectrum and cast onto the moon’s surface.
As a result, expect to see the lunar disk go from a dark gray color during the partial phase of the eclipse to a reddish-orange color during totality. The same effect is at work when the sun turns red at sunset.
The moon’s color during totality can vary considerably depending on the amount of dust in the Earth’s atmosphere at the time. Active volcanoes spewing tons of ash into the upper atmosphere, for instance, can trigger blood-red eclipses.