By Mike Lynch Herald Columnist
So with the income tax deadline coming up this Tuesday many of you have come to the conclusion that you think our ever-loving IRS is bleeding you dry! Well, If you’re up after midnight struggling to find deductions, legitimately and legally of course, the full moon will empathize with you as it turns blood red, or could it be our April full moon being audited?
Seriously though, this Tuesday the moon will start turning red shortly after midnight as we have our first total lunar eclipse visible to the entire continental United States since December of 2011. It’s been quite a drought, but this year we’re making up for it with two total lunar eclipses; the income tax day eclipse this week and another lunar cover-up later this year on Oct. 8.
Let’s pray and hope for clear skies over Everett because it’s great spectacle, especially during the nearly 90 minutes of totality. It’s easy since you don’t need any special equipment to take in the show. You don’t need to view it through a dark welder’s glass or to project the image of the eclipse through a pinhole onto a piece of paper as you do for solar eclipses. It’s perfectly safe to stare directly at lunar eclipses for as long as you want with your naked eyes. A word of caution though … staring at any full moon can bring about a little madness in some people, but let’s face it, you may be mad anyway if you’re cramming to get your taxes done on time. Nondeductible insanity may be setting in.
Lunar eclipses are wonderful events, and even though we haven’t had one in three years, lunar eclipse are also a lot more frequent than solar eclipses. They can be seen anywhere in the world where the full moon is visible during the time of the eclipse.
As you can see in the diagram, lunar eclipses occur when the moon, in its monthly orbit around our Earth, passes through the shadow produced by our planet. This can only happen when the moon is full. Normally with full moons the side of the moon facing the Earth is in full sunshine, but during a lunar eclipse the moon slips into Earth’s shadow. This doesn’t happen every time there’s a full moon though, because the moon’s orbit around the Earth is inclined by five degrees to the Earth’s orbit around the sun.
Most months the full moon misses the 6,000-mile-wide shadow, known as the umbra, but not this coming Tuesday morning.
The great lunar cover up gets started at 10:57 p.m. when the moon makes its first contact with the umbra shadow in the southwest sky. You’ll start to notice the left side of the moon begin to darken. The partial eclipse is on and the moon sinks deeper into the umbra, sliding from right to left.
By 12:06 a.m. the moon’s disk will be completely into the umbra shadow and stays in there until 1:25 a.m.. After that the moon commences its slow exit from the umbra and is completely free from the shadow by 2:33 a.m. The eclipse officially ends and you’ll have a chance to take that power nap before you have to go to school or work, or get back to your unrelenting taxes.
The moon doesn’t totally black out during lunar eclipses because the Earth’s shadow is not totally dark. Strained sunlight finds its way to the moon through the shell of atmosphere that covers our Earth. Most of the blue and yellow components of the sun’s light are scattered by Earth’s atmosphere, leaving only a reddish glow sent in the direction of the moon.
This same effect causes reddish-orange sunrises and sunsets and has the same effect on moonrises and moonsets.
Totally eclipsed moons can vary in their degree of redness. Some have more of an orange hue and some can be a much darker shade of red.
It really depends on atmospheric conditions. The murkier the atmosphere from where you’re watching, the darker the eclipse. How red and how dark the moon will get Tuesday morning is just something you’ll just have to wait and see. It’s all part of the fun of witnessing lunar eclipses.
As a huge bonus, while you’re watching the eclipse early Tuesday you can’t help but notice two bright stars next to the eclipsed moon. The star just to the lower right of the shadowy moon is the star Spica, the brightest star in the large but faint constellation, Virgo the Virgin. The eclipsed moon is about 237,000 miles from Earth on Tuesday morning, but Spica is much, much farther away at nearly 263 light years distant. Just one light year, the distance a beam of light travels in one year, is nearly 6 trillion miles! The light you see from Spica left that star in 1751, before our founding fathers signed The Declaration of Independence.
There’s another even brighter “star” a little farther away from the moon, to the upper right with a very distinct bright orange-red hue.
That’s actually the planet Mars at a little over 57 million miles away, the closest it’s been to Earth in more than two years. As I told you last week Mars is in what astronomers call opposition, when it’s at the opposite end of the sky from the sun, just like a full moon, and Mars is at its minimum distance to Earth in a 26-month cycle. If you have a small to moderate telescope check out Mars. You may get a look at the surface features on the planet, but don’t have too high of expectations. At best the valleys and mountain ranges will show up only as fuzzy dark patches on the ruddy surface.
Don’t miss the great 2014 income tax lunar eclipse show Tuesday morning, co-starring Mars and the bright star Spica, even if it taxes your beauty sleep.
Mike Lynch is an amateur astronomer and professional broadcast meteorologist for WCCO Radio in Minneapolis and is author of the book, “Stars, a Month by Month Tour of the Constellations” published by Adventure Publications available at bookstores at http://www.adventurepublications.net
If you have any astronomical questions or want me to write about something you’re seeing the night sky drop me a line at firstname.lastname@example.org
The Everett Astronomical Society welcomes new members and puts on public star parties. Their website is www.everettastro.org