2018 starts with a “supermoon,” which refers to a full or new moon occurring near the time of perigee (Moon’s closest approach to Earth). There’s a full moon on New Year’s Day 2018, and on the same day, the Moon is also near that closest point of its elliptical orbit around the Earth. As a result, this full moon will occupy a bigger-than-average patch of our sky. A supermoon’s apparent diameter is about 7% bigger (and its apparent area on the sky is about 14% bigger) than average. This means that it provides noticeably more reflected light to us earthlings. Below is a composite photograph comparing half of a supermoon (on the right) with half of a typical full moon (left).

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(Photo by Marcoaliaslama – Own work, CC BY-SA 3.0. https://commons.wikimedia.org/w/index.php?curid=14651085. In case you are a photographer, here are full details: The "supermoon" of March 19, 2011 (right), compared to a rather "average" moon of December 20, 2010 (left): note the size difference. Images by Marco Langbroek, the Netherlands, using a Canon EOS 450D + Carl Zeiss Jena Sonnar MC 180mm lens.)

This New Year’s full moon could even be called a “super-duper-moon” because not only is the Moon especially close to the Earth, but the Earth is also near perihelion (the point of its orbit that’s closest to the Sun). This means that the Moon is catching and reflecting a slightly greater amount (about 2% more) of the Sun’s light than average.

In addition, on New Year’s Day, the Moon is nearly 20 degrees north of the celestial equator, which means it will be relatively high in the sky at midnight. Taken together, these factors mean that the full moon on the night of January 1 will be a doozy!

In January 2018, there’s also a full moon on January 31. (The Moon’s phase is exactly full at 8:27 on the morning of the 31st.) When two full moons occur in a month, the second one is referred to as a “blue moon.” (This only happens occasionally – hence the phrase “once in a blue moon”.)

The blue moon of January 31 has another claim to our attention: it undergoes a total lunar eclipse. Unlike solar eclipses, which can only be seen by observers near the path of totality, the eclipsed Moon can be seen from an entire hemisphere of the Earth. Since the lunar eclipse starts shortly before 6 Eastern time on the morning of the 31st and doesn’t become total until nearly 8 AM, we won’t have a really good view from the Sunnyside campus. But if you’re an early riser, watch the full moon “fade out” before it sets on the morning of the 31st. Among the stars, the full moon will be sitting in the faint constellation Cancer the Crab. (See the map below, obtained as a screenshot from TheSkyLive.com)

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As the moonlight fades due to the eclipse, you may notice the sky darken and the medium-bright star Regulus (Alpha Leonis) in the spring constellation Leo may appear to get brighter. (Regulus is at the base of the backwards question mark that traces the mane of Leo the Lion.) But here at Sunnyside, the sky will be starting to brighten due to morning twilight, and the Moon will set in the west before the eclipse reaches totality.

Because Hawaii’s time is 5 hours behind ours, Honolulu would be a better location than Sunnyside for viewing the January 31st lunar eclipse. Come to think of it, at the end of January, Hawaii might be a better place than the Shenandoah Valley for doing many things!

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Hau’oli Makahiki Hou (“how-oh-lee mah-kah-hee-kee ho”) That’s Hawaiian for “Happy New Year”!

--Bill Ingham