Austrian study debunks notion that full moon causes more workplace injuries
VIENNA, Austria: Ever whacked your thumb with a hammer, or wrenched your back after lifting a heavy box, and blamed the full moon? It's a popular notion, but there's no cosmic connection, Austrian researchers said Tuesday.
Robert Seeberger, a physicist and astronomer at Austria's Ministry of Economic Affairs, said a team of experts analyzed 500,000 industrial accidents between 2000 and 2004 and found no link to lunar activity.
"The full moon does not unfavorably affect the likelihood of an accident," Seeberger said.
The study, released Tuesday by the General Accident Insurance Office, said that on average there were 415 workplace accidents registered per day — yet on days when the moon was full, the average actually dropped to 385.
The lunar influence theory dates at least to the first century, when Pliny the Elder wrote that his observations suggested "the moon produces drowsiness and stupor in those who sleep outside beneath her beams."
Seeberger, who advises the Austrian government on accident prevention, said he and fellow researcher Manfred Huber decided to take a closer look because the full moon theory kept surfacing "again and again."
They also checked for a possible interplay between the rate of accidents and the position of the moon relative to Earth, theorizing that gravity might have some effect in tripping people up at work.
But the moon orbits the planet in almost a perfect circle, and there was also no statistically significant relationship between the accident rate and the moon's closest proximity to Earth.
There were an average 400 accidents on days when the moon nudged closest, the study found, compared with an average 396 per day at other times.
"If the force of gravity were responsible for the assumed influence, then the effect would be greatest in the nearest-to-Earth point of orbit," Seeberger said.
Past studies have differed on whether the full moon affects humans by subtly influencing "biological tides."
A landmark study published in 1984, in the British Medical Journal examined the incidence of crimes reported to police from 1978-82 in three locations in India — one rural, one urban, one industrial — and found a spike in crime on full moon days compared with all other days.
But another study, done in Canada in 1998 by University of Saskatchewan researchers, looked at traffic accidents that caused property damage or nonfatal injuries over a nine-year period and found no relationship to the lunar phase.
Most scientists agree that at nearly 385,000 kilometers (239,240 miles) away, the moon is simply too distant — and human beings too small — for it to have any significant effect.
"There's no real reason why it should," said D. John Hillier, a professor of astronomy at the University of Pittsburgh who was not associated with the Austrian study.
"It's often probably just cases of people remembering that there happened to be a full moon when something occurred," he said. "When nothing special happens, they tend not to notice what the moon is doing. So this selective memory just keeps the legend going."
Philip Plait, a former Hubble Space Telescope astronomer who runs http://www.badastronomy.com — a Web site that tries to clear up misunderstandings about the cosmos — says the pull of the moon's gravity is no greater when it's full — it's just easier to see.
"The moon does have a profound affect on Earth," Plait said. "It powers our tides, changes the Earth's spin, and provides light at night. But there are no physical effects on humans themselves."
"People read about this idea, and it makes some sort of sense," he said. "We're raised with stories of werewolves, and the power of the full moon on romance, and they believe it."