We will have six supermoons in 2015, and the first of the bunch is to fall on January 20, 2015.
What, you say? Supermoon? But the moon isn’t anywhere near full on this date! That’s right. This isn’t a full supermoon. Rather, it’s a new supermoon. In fact, the new moons on January 20, February 18 and March 20 all qualify as supermoons. Follow the links below to learn more about the supermoons of 2015.
What is a supermoon? The term supermoon didn’t come from astronomy. We used to call these moons perigee new moons or perigee full moons. Perigee means “near Earth.” An astrologer, Richard Nolle, is credited with coining the term supermoon. He defines them as:
. . . a new or full moon which occurs with the moon at or near (within 90% of) its closest approach to Earth.
That’s a very generous definition, and it’s why supermoons are common in popular culture. According to Nolle’s definition, the year 2015 gives us a total of six supermoons: the new moons of January, February and March, and the full moons of August, September and October.
What time is the January 20 new moon? How close to perigee? The January 20 moon is new at 13:14 UTC. Lunar perigee – the moon’s nearest point to Earth for the month – happens about 1 day and 7 hours after new moon, on January 21, at 20:06 UTC.
The February new moon will more closely coincide with lunar perigee, to present the closest new supermoon of the year – and the second-closest overall. The absolute closest will be the full moon supermoon of September 2015. The February 18 moon will be new at 23:47 UTC, and lunar perigee will occur less than 8 hours afterwards, on February 19 at 7:29 UTC.
The March new moon will come on March 20 at 9:36 UTC, or about 14 hours after reaching lunar perigee (March 19, at 19:38 UTC).
Spring tides accompany January 2015’s supermoon. Will the tides be larger than usual at the January, February and March new moons? Yes, all new moons (and full moons) combine with the sun to create larger-than-usual tides, but perigee new moons (or perigee full moons) elevate the tides even more.
Each month, on the day of the new moon, the Earth, moon and sun are aligned, with the moon in between. This line-up creates wide-ranging tides, known as spring tides. High spring tides climb up especially high, and on the same day low tides plunge especially low.
The January 20 extra-close new moon will accentuate the spring tide, giving rise to what’s called a perigean spring tide. If you live along an ocean coastline, watch for high tides caused by the January, February and March 2015 new moons – or supermoons.
Will these high tides cause flooding? Probably not, unless a strong weather system accompanies the perigean spring tide. Still, keep an eye on the weather, because storms do have a large potential to accentuate perigean spring tides.
Can I see the January 20 supermoon? Don’t expect to see the new moon on January 20 – or on February 18 or March 20 (unless you’re at the right place on Earth to witness the March 20 solar eclipse). At the vicinity of new moon, the moon hides in the glare of the sun all day long, rising with the sun at sunrise and setting with the sun at sunset. On the other hand, if you were on the moon looking at Earth, you’d see a full Earth.
The full moon on September 2015 presents the closest supermoon of the year (356,877 kilometers or 221,753 miles).
However, the new moon on February 18 isn’t far behind, featuring the year’s second-closest. At a distance of 357,098 kilometers or 221,890 miles, the new supermoon on February 18 lies only about 200 kilometers farther away than the September 28 full supermoon. What’s more, the September 28 supermoon will present the final total lunar eclipse of a lunar tetrad – also known as a Blood Moon.
Farthest full moon of 2015 on March 5. One fortnight (approximately two weeks) after the year’s nearest new moon on February 18, it’ll be the year’s farthest and smallest full moon on March 5, 2015. People are calling this sort of moon a micro moon.
Bottom line: The first supermoon of 2015 comes when the moon turns new on January 20, 2015! No, you won’t see this moon, because the new moon hides in the glare of the sun, but you might discern the higher-than-usual tides along the ocean shorelines.