In a few days (March 19) the Moon will enter a “maximal perigee” — bringing it closer to the Earth than it has been in over 18 years. The average distance between the the Earth and the Moon is about 238, 000 miles (382,900 km) and this current perigee will bring it around 17,000 miles (about 10, 500 27,500 km) closer.
It is believed that the effect of the perigee will be enhanced by the fact of a full moon also occurring at the same time.
This tighter orbit is believed by some to mean a dramatic increase in tidal forces and this current pass has been dubbed a “super moon” by an astrologer named Richard Nolle.
The same astronomer astrologer has also predicted that such a close perigee would/must somehow perturb the earth’s (tectonic) integrity so much that it will trigger major earthquakes and even volcanoes (not simply severe storms). Although he is not clear on the exact lunar-geo-mechanisms that would produce these quakes, never-the-less this lunar-induced disaster scenario quickly set the Web abuzz with yet another wave of doom-and-gloom “apocalypticism.”
Timing is everything.
And then, this past Friday the world learned of the disastrous news from Japan. Is the impending “super moon” somehow responsible for this massive quake…and, are more on the way?
As to the first question…
Not likely, according to scientist Jim Garvin of NASA’ s Goddard Space Flight Center in Greenbelt, Maryland, who notes that the moon’s effects on the Earth have been extensively studied over many decades, and who also issued a press release on the causes of the supermoon.
Quoting from the release:
“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 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…” – Jim Garvin, Goddard Space Flight Center, NASA
The gravitational “pull” of the Moon, in combination with the Earth’s rotation and movement in space (and the pull of the Sun on both bodies), is the complex cause of tidal forces (which we see as high, low, spring/leap, and neap tides) but the energy of this force is no match for the energy coming from within our planet. Garvin writes:
“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 drive plate tectonics).”
So, the visual effect of the full moon may make it seem bigger (like a “big pizza pie”, as the song goes), even though the difference in distance is only a few percent — an amount (and a “gravitational effect”) small enough that most would hardly ever notice, were it a new Moon, and were there no would-be, latter-day Nostradamuses.
As to the second question (are more on the way?)…
We should always look to where we live first before we look to the heavens to solve Earthly mysteries; Japan sits atop a tectonic plate ridge that is continuously undergoing subduction and elevation, the main causes of earthquakes (and volcanoes) in this region of the Pacific ‘ring of fire’.
More things in Heaven and Earth, Horatio.
Fun Fact: Gravitational anomalies slightly distorting the orbits of the Lunar Orbiters led to the discovery of mass concentrations (dubbed mascons), beneath the lunar surface caused by large impacting bodies at some remote time in the past. These anomalies are significant enough to cause a lunar orbit to change significantly over the course of several days. [And yet, we don’t notice these changes at all]. (source: wikipedia.org).
Some source material for this post came from NASA Scientist Explains Science Behind ‘Supermoon’ Phenomenon.
Top Image: A full moon is visible in this view above Earth’s horizon and airglow, photographed by Expedition 10 Commander Leroy Chiao on the International Space Station. Credit: NASA
Lunar Perturbation Diagram: Geologician (slight correction by Homunculus 2); Creative Commons Attribution 3.0
Lunar Phase Animation: Tomruen
