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How to see the last 'super blood wolf moon' lunar eclipse for 18 years

Everything you need to know about the rare conjunction of celestial events this weekend.

A 2018 super blood moon as seen from Great Sand Dunes National Park and Preserve in Colorado.

NPS/Patrick Myers

There's going to be a legitimately good reason to howl at the moon on the evening of Sunday, Jan. 20 (or the early morning of Monday, Jan. 21 in Europe). Don't worry, you're not going to grow fur or claws. It's just some rare cosmic geometry that will turn a big ol' full moon a spooky shade of crimson for a spell.

Three elements make a "super blood wolf moon," but the part that makes it so rare it happens only three times this century is the least impressive. A "wolf moon" is simply the folk name for a moon that happens in the month of January.

Take that away and you've got a super blood moon, which is a total lunar eclipse that happens at "perigee syzygy." I know some people mistrust words like syzygy without any proper vowels, so let's stick with supermoon from here on.

A total lunar eclipse is referred to as a blood moon because when the sun, Earth and moon all line up briefly, the shadow of the Earth casts a reddish shadow on its lone natural satellite. Then there's the supermoon part, meaning the moon is at the point in its orbit where it's just a little bit closer to us, making it seem 10 to 15 percent larger in the sky.

We get two to five supermoons every year, while the gap between blood moons is anywhere from six months to about three years. You can also plan on around one to five super blood moons each decade, but they only fall in January three times this century (the third and final 21st-century super blood wolf moon barely qualifies, since it falls at the very end of the month on Jan. 31, 2037).

The entirety of the total lunar eclipse on Sunday night will be visible from all of North and South America, save for the Aleutian Islands in Alaska. West Africa and the western half of Europe will also get to take in most of the show. 

Starting at around 7:34 p.m. PT or 10:34 p.m. ET Sunday, a partial eclipse will begin, with the full eclipse starting a little over an hour later. You can safely look at the blood moon from anywhere skies are clear enough, unlike solar eclipses that require special eye protection in most cases. The main event lasts about an hour. 

If skies don't cooperate or you can't be bothered to step outside for some reason to see it for yourself, you can catch the livestream from the Virtual Telescope Project in Rome below. There's also a handful of other eclipses still to come in 2019.

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