There’s long been anxiety over total lunar eclipses, also referred to as ‘blood moons‘ for the reddish hue that the shadow of the Earth casts on the full moon during the not-really-that-rare event (it happens about every one to three years). Often thought of as a bad omen by various prognosticators of assorted religious, conspiratorial and otherwise paranoid stripes, it’s sometimes claimed that a lunar eclipse can “trigger” natural disasters like earthquakes and volcanic eruptions.
There’s a certain logic to this notion, and even some scientific evidence to back it up, but there is absolutely no reason for increased concern about the coming ‘super blood wolf moon’ set to be observable from the Americas and western Europe the evening of January 20 and early morning of January 21.
Before we get into why you shouldn’t worry, let’s first break this event down, word by word. The super is as in ‘supermoon‘, which is when a full moon occurs while the moon is at or near perigee – its closest point to us as it orbits Earth. Blood is as in blood moon, mentioned above, and wolf moon is just the nickname for a full moon in January, so that part has no real bearing on anything.
Basically we’re going to have a total lunar eclipse, which means the sun, earth and moon will be in a straight line for a short time, while the moon is also near perigee. Intuitively, it doesn’t seem completely unreasonable that this alignment could affect our planet somehow.
In fact, there is evidence that the tidal effect of the moon on the Earth – literally the moon’s gravitational pull on our planet, which is strongest during full and new moons – does impact seismic activity.
A 2016 study in Nature Geoscience found that the tides that occur during full and new moons may be connected to a slightly higher likelihood of high magnitude earthquakes around the world. But there remains a complex web of factors that trigger tremors and determine their intensity. Also, more recent analysis of earthquakes with a magnitude greater than 8.0 found no correlation with the lunar cycle.
According to the USGS, earthquakes may be up to three times more likely during high tides, but the agency cautions that means they’re still very unlikely.
“You must stop and realize that the background probability is, in general, very low in a given place and year (fractions of a percent), so that raising this tiny probability by a factor of 3 during high tides still results in a very tiny probability.”
The overall odds of an earthquake striking a particular location during a full moon remain so small that worry about a moon-quake connection is kind of like leaving town every time there’s a thunderstorm because you’re worried of the increased risk of a plane crashing into your house.
The same goes for any added gravitational influence that comes with a supermoon: the difference is just tiny, especially when we’re talking about affecting huge tectonic plates and deep pockets of magma.
The USGS has also said that there may be a correlation between the lunar cycle and eruptions of Hawaiian volcanoes, but with the same caveat that attempting to predict eruptions around tides or the moon would be absurd.
“In the Hawai’i example of 52 eruptions since January 1832, there have been nearly 3,900 tidal maximums, of which roughly 3,850 of them went by without causing an eruption. Statistically, this is about a one percent chance that any tidal maximum will affect the start of an eruption.”
As for the eclipse part of the equation, consider that the sun, earth and moon lining up doesn’t change the gravitational impact of the sun on the Earth – we’re still just as far away from our star as normal and there is certainly no evidence that the geometry of a straight line has geological implications.
Previous predictions of eruptions tied to lunar events have often failed to come true, while retrospective “connections” tend to be no more than prime examples of confirmation bias. I recently saw one seer online claiming that last summer’s total lunar eclipse “caused” the brutal hurricane season that followed. Pick any event, pick a disaster that happened after that event, claim the two are connected and you can play this game too.
More than anything, just keep in mind that supermoons and lunar eclipses are both relatively common celestial events. They’ve come and gone countless times without ushering in the apocalypse. Rather than worrying, better to spend your time heading outside and taking in the spectacular view.