Fourth full moon of 2019 set for April 19

A full moon occurs every 29.5 days and is when the Moon is completely illuminated by the Sun’s rays. It occurs when Earth is directly aligned between the Sun and the Moon. The early Native Americans did not record time using months of the Julian or Gregorian calendar. Instead tribes gave each full moon a nickname to keep track of the seasons and lunar months.

Most of the names relate to an activity or an event that took place at the time in each location. However, it was not a uniform system and tribes tended to name and count moons differently. Some, for example, counted four seasons a year while others counted five. Others defined a year as 12 moons, while others said there were 13.Colonial Americans adopted some of the moon names and applied them to their own calendar system, which is why they are still in existence today, according to the Farmer’s Almanac.

This moon is important because it is used to fix the date of Easter, which is always the Sunday after the first full moon following the spring equinox. This year, that moon appears on Friday April 19, which means Easter Sunday falls two days later, on Sunday April 21.Meanwhile, the full moon is associated with an increased risk of fatal motorcycle crashes in the United States, the United Kingdom, Canada and Australia, according to a study published in The BMJ.

The researchers said their findings might encourage motorcyclists to ride with extra care during a full moon and, more generally, to appreciate the power of seemingly minor distractions at all times. Motorcycle crashes are a common cause of death worldwide. Momentary distraction is a common contributor to road traffic deaths. A full moon occurs about 12 times a year, appearing big and bright in the night sky – and is therefore a potential distraction for roads users.

Another study published in the journal Nursing Research, however, noted that the absence of a lunar influence on human affairs has been demonstrated in the areas of automobile accidents, hospital admissions, surgery outcomes, cancer survival rates, menstruation, births, birth complications, depression, violent behaviour, and even criminal activity.

Even though a 40-year-old University of California Los Angeles (UCLA), United States (U.S.), study demonstrated that the timing of births does not correlate in any way with the lunar cycle, the belief in a lunar effect has persisted. A 2004 study in a nursing journal, for example, suggested that the full moon influenced the number of hospital admissions in a medical unit in Barcelona, Spain.

Another study published in Current Biology has debunked popular beliefs about the influence of the moon on humans widely exist. Many people report sleeplessness around the time of full moon. In contrast to earlier studies, scientists from the Max Planck Institute of Psychiatry in Munich did not observe any correlation between human sleep and the lunar phases. The researchers analyzed preexisting data of a large cohort of volunteers and their sleep nights. Further identification of mostly unpublished null findings suggests that the conflicting results of previous studies might be due to a publication bias.

For centuries, people have believed that the moon cycle influences human health, behaviour and physiology. Folklore mainly links the full moon with sleeplessness. Also, astronomers find evidence of a planet with a mass almost 13 times that of Jupiter.Giant Magellan Telescope (GMT), in Chile’s Atacama Desert, will help to obtain answers on the formation and evolution of these exotic environments, as well as the possibility of life there.

In the past three decades, almost 4,000 planet-like objects have been discovered orbiting isolated stars outside the Solar System (exoplanets). Beginning in 2011, it was possible to use United States Aeronautic Space Agency’s (NASA’s) Kepler Space Telescope to observe the first exoplanets in orbit around young binary systems of two live stars with hydrogen still burning in their core. Brazilian astronomers have now found the first evidence of the existence of an exoplanet orbiting an older or more evolved binary in which one of the two stars is dead.

The study resulted from a postdoctoral research project and a research internship abroad, both with scholarships from São Paulo Research Foundation – FAPESP. Its findings have just been published in the Astronomical Journal, owned by the American Astronomical Society (AAS).

Leonardo Andrade de Almeida (https://bv.fapesp.br/en/pesquisador/265214/leonardo-andrade-de-almeida), first author of the article, told as follow: “We succeeded in obtaining pretty solid evidence of the existence of a giant exoplanet with a mass almost 13 times that of Jupiter [the largest planet in the Solar System] in an evolved binary system. This is the first confirmation of an exoplanet in a system of this kind.”

Almeida is currently a postdoctoral fellow of the Federal University of Rio Grande do Norte (UFRN), having conducted postdoctoral research at the University of São Paulo’s Institute of Astronomy, Geophysics and Atmospheric Sciences (IAG-USP), where he was supervised by Professor Augusto Damineli, a coauthor of the study.Clues followed by the researchers to discover the exoplanet in the evolved binary called KIC 10544976, located in the Cygnus constellation in the northern celestial hemisphere, included variations in eclipse timing (the time taken for each of the two stars to eclipse the other) and orbital period.

“Variations in the orbital period of a binary are due to gravitational attraction among the three objects, which orbit around a common center of mass,” Almeida said.Orbital period variations are not enough to prove the existence of a planet in the case of binaries, however, because binary stars’ magnetic activity fluctuates periodically, just as the Sun’s magnetic field changes polarity every 11 years, with turbulence and the number and size of sunspots peaking and then declining.

“Variations in the Sun’s magnetic activity eventually cause a change in its magnetic field. The same is true of all isolated stars. In binaries, these variations also cause a change in orbital period due to what we call the Applegate mechanism,” Almeida explained.

To refute the hypothesis that variations in the orbital period of KIC 10544976 were due only to magnetic activity, the researchers analyzed the effect of eclipse timing variation and the magnetic activity cycle of the binary’s live star.KIC 10544976 consists of a white dwarf, a dead low-mass star with a high surface temperature, and a red dwarf, a live (magnetically active) star with a small mass compared to that of our Sun and scant luminosity due to low energy output. The two stars were monitored by ground-based telescopes between 2005 and 2017 and by Kepler between 2009 and 2013, producing data minute by minute.

“The system is unique,” Almeida said. “No similar system has enough data to let us calculate orbital period variation and magnetic cycle activity for the live star.”Using the Kepler data, they were able to estimate the magnetic cycle of the live star (red dwarf) based on the rate and energy of flares (large eruptions of electromagnetic radiation) and variability due to spots (regions of cooler surface temperature and hence darkness caused by different concentrations of magnetic field flux).

Analysis of the data showed that the red dwarf’s magnetic activity cycle lasted 600 days, which is consistent with the magnetic cycles estimated for low-mass isolated stars. The binary’s orbital period was estimated at 17 years.

“This completely refutes the hypothesis that orbital period variation is due to magnetic activity. The most plausible explanation is the presence of a giant planet orbiting the binary, with a mass approximately 13 times that of Jupiter,” Almeida said.

How the planet orbiting the binary was formed is unknown. One hypothesis is that it developed at the same time as the two stars billions of years ago. If so, it is a first-generation planet. Another hypothesis is that it formed out of the gas ejected during the death of the white dwarf, making it a second-generation planet.

Confirmation of its status as either a first- or second-generation planet and its direct detection as it orbits the binary could be obtained using the new generation of ground-based telescopes with primary mirrors exceeding 20 meters, including the Giant Magellan Telescope (GMT) installed in Chile’s Atacama Desert. The GMT is expected to see first light in 2024.