Truly rare Super Blue Blood Moon Wednesday

It's a rare astronomical trifecta Wednesday morning. The Super Blue Blood Moon is on the way.

The Jan. 31 full moon is special for three reasons: it’s the third in a series of “supermoons,” when the Moon is closer to Earth in its orbit -- known as perigee -- and about 14 percent brighter than usual. It’s also the second full moon of the month, commonly known as a “blue moon.” The super blue moon will pass through Earth’s shadow to give viewers in the right location a total lunar eclipse. While the Moon is in the Earth’s shadow it will take on a reddish tint, known as a “blood moon.”

Let's break down this rare celestial phenomenon.

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Supermoon

So called supermoons occur when the moon's orbit is closer to earth. NASA calculates Wednesday's moon will be 223,068 miles from Earth. That's about 5,000 miles closer then than the usual 238,855 miles.

Closer means brighter. NASA estimates Wednesday's moon will be about 14 percent closer and up to 30 percent brighter than your typical moon.

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NASA

Blue moon

A so called Blue Moon is defined in several ways. Wednesday's full moon is the second on the month. NASA elaborates.

According to modern folklore, a Blue Moon is the second full moon in a calendar month. Usually months have only one full moon, but occasionally a second one sneaks in. Full moons are separated by 29 days, while most months are 30 or 31 days long; so it is possible to fit two full moons in a single month. This happens every two and a half years, on average.

Blood moon

The term blood moon comes from the sometimes copper red tint of the moon during a lunar eclipse. Wednesday morning's lunar eclipse occurs over Minnesota as the moon is setting right around sunrise.

lunar_eclipse_01182018a
NASA

First time in 152 years

This week's Super Blue Blood Moon is rare. The last time this trifecta occurred over North America was 152 years ago in 1866.

Here are the eclipse details for Minneapolis via timeanddate.com.

1 31 ec
timeanddate.com

Minnesota viewing iffy

The latest cloud forecast for Wednesday morning favors good viewing in central Minnesota. Clouds may linger over the Twin Cities. But St. Cloud, Brainerd, and Fargo, N.D., have a better chance for clear skies.

Here's the National Oceanic and Atmospheric Administration's Global Forecast System total cloud fraction at 6 a.m. Wednesday.

1 29 cf
NOAA GFS model total cloud fraction forecast for 6 am Wednesday via tropical tidbits.