Will March 19 'supermoon' trigger disasters?

By Natalie Wolchover




space.com
And found at:
http://www.msnbc.msn.com/id/41997880/ns/technology_and_science-space/

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 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."

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?

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
measurable 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
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.'"

The bottom line is, the upcoming supermoon
won't cause a preponderance of earthquakes,
although the idea isn't a crazy one.

"Earthquakes don't respond as much to the
tides as you'd think they would. There should
actually be more of an effect," said Vidale.

Most natural disasters have nothing to do with
the moon at all. The Earth has a lot of pent up
energy, and it releases it anytime the buildup
gets too great. The supermoon probably won't
push it past the tipping point, but we'll know
for sure, one way or the other, by March 20.