The smallest full moon of the year – which we’ve heard called the micro-moon or mini-moon – is tonight, January 15-16, 2014. This January full moon – smallest full moon of 2014 – lies about 50,000 kilometers (30,000 miles) farther away from Earth than will the year’s closest full moon – the full supermoon of August 10, 2014.
The crest of the moon’s full phase comes on January 16, 2014 at precisely 4:52 UTC. Although the full moon occurs at the same instant all around the world, our clock reads differently in different time zones. In the United States, the moon turns exactly full on Wednesday, January 15, at 11:52 p.m. EST, 10:52 p.m. CST, 9:52 p.m. MST or 8:52 p.m. PST.
No matter where you live worldwide, look for the moon to appear full all night long, lighting up the nighttime from Wednesday’s dusk until Thursday’s dawn. As with any full moon, this January 2014 moon rises pretty much opposite the sun at sunset and sets opposite the sun at sunrise.
In North America, we often call the January full moon by the names of Old Moon, Moon after Yule or Wolf Moon. But in recent years, we’ve also heard the term micro-moon to describe the year’s smallest full moon. It’s not a name (like Wolf Moon). It’s not bound to a particular month or season. It’s just a term to describe the year’s smallest moon.
The micro-moon returns about 48 days later with each passing year, meaning that, in 2015, the years smallest full moon will come on March 5. In 2016, it’ll come on April 22. In 2017, the year’s smallest full moon will come on June 9. And so on, no doubt until our earthly calendars are long forgotten.
What is a micro-moon? We at EarthSky have always referred to the year’s smallest full moon as an apogee full moon, and have been introduced to the term micro-moon only fairly recently. Micro-moon seems to be entering into the general lexicon, probably because it rolls off the tongue more easily than apogee full moon. As some indication of the appellation’s growing popularity, we’ve found that the NASA Astronomy Photo of the Day and timeanddate.org sites both like to call the smallest full moon a micro-moon.
Every month, the moon swings out to lunar apogee – the farthest point in its orbit – and then some two weeks later swings to lunar perigee – the closest point to Earth in the moon’s orbit. Whenever the full moon coincides with apogee, we have an apogee full moon – or Micro Moon. However, the two January new moons bracketing the micro-moon enjoy the supermoon designation, because both new moons closely align with lunar perigee – the moon’s closest point to Earth in its orbit.
In many respects, the micro-moon is the antithesis to the supermoon. The micro-moon, or the full moon aligning with apogee, is the polar opposite of a full moon supermoon, the full moon coinciding with perigee. Every month for the next seven months, the full moon will come closer and closer to Earth. So the seventh full moon after the January 2014 micro-moon will give us the year’s most “super” supermoon on August 10, 2014. At that time, the year’s biggest moon will be only 356,896 kilometers (221,765 miles) away, about 50,000 kilometers (30,000 miles) closer than tonight’s Micro Moon.
By the way, the moon’s mean distance from Earth is about 384,400 kilometers (238,855 miles). As the full moon comes closer and closer to Earth with each passing month, April will give us a full moon near the moon’s mean distance on April 15, 2014. Then we’ll have the year’s closest full moon on August 10, 2014. But for now, enjoy the micro-moon – the year’s smallest full moon – on the night of January 15-16.
Bottom line: The micro-moon or mini-moon – smallest full moon of 2014 – lies about 50,000 kilometers (30,000 miles) farther away from Earth than will the full moon supermoon of August 10, 2014.