Red moon by morning: Total lunar eclipse on tax day

If you are already planning to be up early on April 15, setting the alarm for just a few hours earlier - or staying up a little later - might be worth your while in the most celestial way: A total eclipse of the moon will occur between 1:58 a.m. and 5:33 a.m., according to Skip Bird, outreach director for the Westminster Astronomical Society.

The result of the moon passing through the earth's shadow, a total lunar eclipse is safe to view with the naked eye, unlike a solar eclipse, according to Bird, and the only pieces of equipment necessary to view a lunar eclipse are a pair of eyes, a comfortable chair and perhaps some hot chocolate.

"With a solar eclipse, you are looking at the sun, which is like a light bulb," he said. "A lunar eclipse is the opposite. With a lunar eclipse, you are looking at the shadow, not the light bulb, so it is safe to look at."

The eclipse will proceed in phases with the earliest, barely noticeable changes coming around 1 a.m., according to Bird, as the moon slips into the earth's penumbral shadow, the gray, less opaque border of the shadow earth casts into space, which will dim the lunar luminosity. Just before 2 a.m. will begin the partial eclipse, when the curved, dark core of earth's shadow - the umbral shadow - can be seen moving across the face of the moon.

"It will take it 40 to 45 minutes to go completely dark, that is, it goes from bright white, to some shade of red, or pink or orange," Bird said. "The partial eclipse starts at 1:58 a.m. and totality begins at 3:07 a.m."

The moon changes color rather than going black during totality, because it is still illuminated by the light rays that are bent through earth's atmosphere from the day side, according to Curtis Roelle, chairman of the Westminster Astronomical Society. From the point of view of an astronaut on the moon, the event would actually be an eclipse of the sun by the earth and the earth would be seen as a black circle, all aflame around the perimeter with the simultaneous sunrises and sunsets of the world.

The period of totality, when the moon is completely in the earth's umbral shadow, will last from 3:07 a.m. until 4:25 a.m., Bird said, when the process will reverse itself.

Although a lunar eclipse is easy to view with the naked eye, there can be some benefit to using a telescope such as watching the earth's shadow cross specific craters on the moon's surface. For those who do not have a telescope, a group of astronomers led by Bird will be out on the front lawn of the Westminster branch of the Carroll County Public Library beginning at 2 a.m. on April 15 with some telescopes to share.

Those that would like to learn more about the science behind the eclipse, but don't wish to miss their bedtime can attend Only The Shadow Knows, a free, 7:30 p.m. program Bird will lead on April 14 at the library. It will also serve as a primer for those that plan to come out later to get a glimpse of the eclipse.

According to Jim Reynolds, planetarium director at Bear Branch Nature Center, the chance to view a lunar eclipse is special, even if the timing may be inconvenient. For many ancient cultures, an eclipse of any sort was a terrifying event, unpredictable and full of ominous forbearing, but which today can be viewed as beautiful through the light of astronomical understanding.

"It's an event that a lot of small children will remember for the rest of their lives," Reynolds said. "I can remember my father getting me out of bed to see one of these events and being really impressed by it."

According to data on NASA's eclipse webpage, this will be the first total lunar eclipse visible from North America since Dec. 5, 2010. It is also the first in a tetrad, a group of four consecutive total lunar eclipses: The next three eclipses in the tetrad will take place on Oct. 8, 2014, April 4, 2015 and Sept. 28, 2015.

According to NASA's website, the last such tetrad of total lunar eclipses occurred in 2003 and 2004 and the next set after the present tetrad will not occur until 2032 and 2033.

Historical context aside, Roelle said he plans to be up to see the eclipse simply because each one is a unique event in the sky.

"It would be nice if it were on a weekend, but I still plan to get up to see it," he said. "They are fairly rare and each one is different, just because the moon, as it passes through the earth's shadow, it doesn't always pass through the same part of the shadow."

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