On Saturday night, it is once again time for the monthly full moon, more specifically, the clock 23.11 (or 11.11 for the siffermagiskt placed).

people, animals and nature, and in that case, in what way, is probably as old as man himself.

Read more: In the full moon violence

Different kind of psychological problems has since ancient times been associated with the full moon. In Swedish, there is talk of ”mångalenskap”, and the word of madness has also in other languages derived from the word for moon (lunacy, lunático).

There are lots of studies done on the moon’s potential impact. But there is a wide range of effects being studied, and the results are not always clear. In the case they are, it rejects the many times that there would be no måneffekt that can not be explained in any other way. But not always.

A new study at the university of Oulu have examined the frequency of murders in Finland in relation to the phases of the moon during a 54-year-long period, between 1961 and 2014. The period covers approximately 650 full moons.

Often said that acts of violence are more common during the full moon. Professor Simo Näyhäs study, which includes 6.808 murder, show on the contrary that the murders are significantly less during full moon than during the other phases. The difference is 15 per cent. Between the other phases (new moon and crescent) is visible, however, no statistically significant differences.

” the Question has interested me. The idea that the moon has hazardous properties, is very old. There are few good studies, especially when it comes to mordfrekvensen, says Näyhä, who is a professor in public health sciences.

– The general consensus in research is that the moon does not have any effect. But in Germany, for instance, argues even that the full moon triggers the anxiety, and the police usually say that the violence is increasing, and among the health professionals said that patients will be ”crazier” during the full moon. I have never really believed in the public perceptions.

thus, very clearly and exactly the opposite of what could be expected on the basis of the usual perceptions.

– It is difficult to understand why, but my explanation is that it has the light to do, ” says Simo Näyhä.

the thing is that the decline in the number of murders during the full moon has slowed down over time. Between 1961 and 1974 there were 25 percent fewer murders when the moon was full, but after the turn of the millennium is the decline of 10 per cent.

Näyhäs the theory is that the light during the full moon had major significance in the past, when more people lived in the country, and that the change over time depends on urbanization. A certain percentage of those who commit murder refrain when it is bright. Such a crime is easier to commit in the dark, ” he says.

” That light prevents crime is common sense. There is nothing mysterious about it.

at the same time admits Simo Näyhä that it is ”a bit mysterious” to the phenomenon are still there, even if it had been reduced. And the fact that the vast majority of the murders in Finland are committed indoors ”complicates” his explanation. ”The reason for the link remains elusive,” writes Näyhä in its report.

the Decline in the number of murders during the full moon visible in the middle of the curve. Graphics: Simo Näyhä, university of Oulu

the full moon is sleep disorders. Up until a few years ago, few studies have been made, and they drew conflicting conclusions.

But in 2013 found a group of swiss scientists to the people who participated in a sömnstudie fell asleep five minutes later, slept 20 minutes less and spent 30 percent less time in deep sleep when it was full moon than otherwise. The subjects were in a windowless room and had not been told what the study was.

the Results were repeated in broadly in another study the following year.

– There are strong cultural links to the full moon that it would not be surprising if there are effects on sleep. Now it is up to science to explain why, said the uk sömnexperten Neil Stanley for the BBC, in conjunction with the swiss study was published.

study in the u.s. from the 1989 examined the , the three scientists on the number of patients admitted to hospital who have been victims of violent crime were greater during full moon than otherwise. They found no statistically significant difference.

Five years earlier, came a report in which the correlation between the crimes and the phases of the moon were examined in the three cities between 1978 and 1982. The researchers found that the number of crimes was significantly higher during full moon than during the other moon phases.

A study from 2004 looked more closely at the possible månpåverkan on the number of cases of gastro-tarmblödningar. The researchers found that, on average, were more cases during the full moon, especially in men, but since the variation was large across the whole of the lunar cycle, they recommended more research in the subject.

Four years later, four scientists at the university of Glasgow a study that showed a significant increase of the number of medically unexplained cases of stroke during the full moon than during the moon’s other phases. ”The reason for this variation remains elusive,” concludes the researchers.

white rewritten. Bivalve molluscs, ostrons and a number of other marine animal behavior is partly determined by russia in February cycles. Oysters open, for example, more during the new moon and less during the full moon, studies show.

The american dolksvansen, or hästskokrabban, mate during high tide, and as the familiar controls the moon tide. However, it would seem, above all, be the water’s rhythm regulates the dolksvansens behavior, which has been shown in studies where they created ”tides” on the artificial path.