Super Moon

The Dark Side of the Moon. LROC WAC orthographic projection centered at 180° longitude, 0° latitude. Image Source: NASA/Goddard/Arizona State University.

Caption for the above photograph: Because the moon is tidally locked (meaning the same side always faces Earth), it was not until 1959 that the farside was first imaged by the Soviet Luna 3 spacecraft (hence the Russian names for prominent farside features, such as Mare Moscoviense). And what a surprise -­ unlike the widespread maria on the nearside, basaltic volcanism was restricted to a relatively few, smaller regions on the farside, and the battered highlands crust dominated. A different world from what we saw from Earth.

Today marks the last full moon of winter.  It's special in that it is unusually close to the Earth.  The Farmers' Almanac terms the March full moon as the Full Worm Moon:

As the temperature begins to warm and the ground begins to thaw, earthworm casts appear, heralding the return of the robins. The more northern tribes knew this Moon as the Full Crow Moon, when the cawing of crows signaled the end of winter; or the Full Crust Moon, because the snow cover becomes crusted from thawing by day and freezing at night. The Full Sap Moon, marking the time of tapping maple trees, is another variation. To the settlers, it was also known as the Lenten Moon, and was considered to be the last full Moon of winter.

A few days ago, in the wake of the huge Japanese earthquake, a commentator on CNN remarked that the proximity of the Moon to the Earth can affect tsunamis and earthquakes.

Some articles argue similarly that the Moon's proximity to our planet sparked the earthquake:

The Japanese tsunami came just days after warnings that the closeness of the Moon to Earth could cause tidal waves, volcanic eruptions and earthquakes. On March 19, the Moon will be at its closest since 1992. ...

The theory is that the “supermoon” will cause shifts in the Earth’s surface. Previous supermoons took place in 1955, 1974, 1992 and 2005 – all years of extreme weather, supporters of the theory claim.

The Boxing Day tsunami that killed hundreds of thousands of people in Indonesia happened two weeks before the January 2005 supermoon. And on Christmas Day 1974, Cyclone Tracy laid waste to Darwin, Australia. ...

US astrologer Richard Nolle warned about the supermoon, a term he coined in 1979. He said they “have a historical ­association with strong storms, very high and extreme tides and also earthquakes”.

But seismologist Professor George Helffrich of Bristol University branded the theory “nonsense”. He added: The moon has no significant effect on ­earthquake-triggering.”

John S Whalley, geoscience programme manager at the University of Portsmouth, said: “There is no established ­correlation. It is all too easy, with hindsight, to link major ­earthquakes to variations in all sorts of parameters.”

Universe Today agrees.  The Moon did not cause the earthquake in Japan:

Several scientists ... in no uncertain terms, agree that the the upcoming perigee of the Moon — where it is closer than usual in its orbit to Earth — had nothing to do with the earthquake and ensuing tsunami. ... Dr. Jim Garvin, chief scientist at NASA’s Goddard Space Flight Center, has provided some answers to questions about the ‘supermoon’ phenomenon ...

Question: What is the definition of a supermoon and why is it called that?

Garvin: ‘Supermoon’ is a situation when the moon is slightly closer to Earth in its orbit than on average, and this effect is most noticeable when it occurs at the same time as a full moon. So, the moon may seem bigger although the difference in its distance from Earth is only a few percent at such times.

It is called a supermoon because this is a very noticeable alignment that at first glance would seem to have an effect. The ‘super’ in supermoon is really just the appearance of being closer, but unless we were measuring the Earth-Moon distance by laser rangefinders (as we do to track the LRO [Lunar Reconnaissance Orbiter] spacecraft in low lunar orbit and to watch the Earth-Moon distance over years), there is really no difference. The supermoon really attests to the wonderful new wealth of data NASA’s LRO mission has returned for the Moon, making several key science questions about our nearest neighbor all the more important.

Question: Are there any adverse effects on Earth because of the close proximity of the moon?

Garvin: The effects on Earth from a supermoon are minor, and according to the most detailed studies by terrestrial seismologists and volcanologists, the combination of the moon being at its closest to Earth in its orbit, and being in its ‘full moon’ configuration (relative to the Earth and sun), should not affect the internal energy balance of the Earth since there are lunar tides every day. The Earth has stored a tremendous amount of internal energy within its thin outer shell or crust, and the small differences in the tidal forces exerted by the moon (and sun) are not enough to fundamentally overcome the much larger forces within the planet due to convection (and other aspects of the internal energy balance that drives plate tectonics). Nonetheless, these supermoon times remind us of the effect of our ‘Africa-sized’ nearest neighbor on our lives, affecting ocean tides and contributing to many cultural aspects of our lives (as a visible aspect of how our planet is part of the solar system and space).

As for the frightening predictions that the experts are discounting, Space.com has been speculating on astrologers' comments about this so-called Super Full Moon:

On March 19, the moon will swing around Earth more closely than it has in the past 18 years, lighting up the night sky from just 221,567 miles (356,577 kilometers) away. On top of that, it will be full. And one astrologer believes it could inflict massive damage on the planet.

Richard Nolle, a noted astrologer who runs the website astropro.com, has famously termed the upcoming full moon at lunar perigee (the closest approach during its orbit) an "extreme supermoon."

When the moon goes super-extreme, Nolle says, chaos will ensue: Huge storms, earthquakes, volcanoes and other natural disasters can be expected to wreak havoc on Earth. (It should be noted that astrology is not a real science, but merely makes connections between astronomical and mystical events.)

But do we really need to start stocking survival shelters in preparation for the supermoon? ...

The question is not actually so crazy. In fact scientists have studied related scenarios for decades. Even under normal conditions, the moon is close enough to Earth to make its weighty presence felt: It causes the ebb and flow of the ocean tides.

The moon's gravity can even cause small but measureable ebbs and flows in the continents, called "land tides" or "solid Earth tides," too. The tides are greatest during full and new moons, when the sun and moon are aligned either on the same or opposite sides of the Earth.

According to John Vidale, a seismologist at the University of Washington in Seattle and director of the Pacific Northwest Seismic Network, particularly dramatic land and ocean tides do trigger earthquakes. "Both the moon and sun do stress the Earth a tiny bit, and when we look hard we can see a very small increase in tectonic activity when they're aligned," Vidale told Life's Little Mysteries, a sister site to SPACE.com.

At times of full and new moons, "you see a less-than-1-percent increase in earthquake activity, and a slightly higher response in volcanoes."

The effect of tides on seismic activity is greatest in subduction zones such as the Pacific Northwest, where one tectonic plate is sliding under another. William Wilcock, another seismologist at the University of Washington, explained: "When you have a low tide, there's less water, so the pressure on the seafloor is smaller. That pressure is clamping the fault together, so when it's not there, it makes it easier for the fault to slip."

According to Wilcock, earthquake activity in subduction zones at low tides is 10 percent higher than at other times of the day, but he hasn't observed any correlations between earthquake activity and especially low tides at new and full moons. Vidale has observed only a very small correlation.

What about during a lunar perigee? Can we expect more earthquakes and volcanic eruptions on March 19, when the full moon will be so close?

The moon's gravitational pull at lunar perigee, the scientists say, is not different enough from its pull at other times to significantly change the height of the tides and thus the likelihood of natural disasters. ...

"A lot of studies have been done on this kind of thing by USGS scientists and others," John Bellini, a geophysicist at the U.S. Geological Survey, told Life's Little Mysteries. "They haven't found anything significant at all."

Vidale concurred. "Practically speaking, you'll never see any effect of lunar perigee," he said. "It's somewhere between 'It has no effect' and 'It's so small you don't see any effect.'"

For links from astrology sites arguing the opposite point of view, go here and here.  Some commenters on the latter link who are psychically inclined believe that this full moon will rather affect human emotions:

I feel that this phenomenon will not only affect the weather and tides but also human emotions. We are in Pisces right now, a very emotional and psychic time of the year. Anything related to feelings and emotions will be heightened, especially for those who are normally emotional to begin with. This could be either very positive or negative. The positive aspects would include love, compassion, empathy, intuitive connections, and friendship connections. The negative aspects could be anger, fear, sadness/depression, anxiety, and/or violence. I also feel this phenomenon could affect driving, in so much as depth perception. I feel this will be more prevalent at night. Those with night-blindness should take extra care.

Others feel that the effects will be political:

My money is on more political turmoil in oil (Pisces) producing nations, striving to make this a better world (Virgo), through aggressive (Aries) groups breaking through with a common vision (Uranus).

Another commenter thinks of this Super Moon as an occasion for a spirtual purge and realignment:

I think there is another way to look at this….from chaos comes great growth. When the earth shakes things up, it is cleansing trapped and negative energies…It is re-balancing itself. This could be a grand opportunity for us to do the same. Stir up our personal lives a bit and see what shakes free. Examine where we need change, what situation needs to erupt or be washed clean? Full moons are always about manifesting. As we approach the super moon, during the waxing, focus strongly on what it is you want to bring into your life, and then watch it come RUSHING in during the Super Moon! Another thing we can do to ease the discomfort that may occur is to allow energies to flow through you ….like sound flows through a speaker. Don’t attach to your emotions, you don’t have to act on them….just let them flow to help maintain a sense of balance. Concentrate on your crown chakra. Let it be open and free flowing so that all your trapped and negative energy has a clear channel out.

For a blog devoted to the metaphysical effects of this moon, see the blog Megamoon 2011 here.  But to return to the Farmer's Almanac, I see it as a turning point in the calendar.  Whatever its larger meaning, I'm not sad to say farewell to winter.