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The last time the Earth began to cool was just over 100,000 years ago, culminating in 20,000 years later when the Arctic ice spread so that it approached the equatorial latitudes. Apart from the global warming that the planet is experiencing today, this forces us to suppose that if the rule that has been repeated for more than a million years is replicated again, it will lead to a new climate crisis in human society.
One of the reasons given below for the gradual cooling of the temperature is that while the Earth changes and tilts its orbit every 100,000 years, it faces an increasingly dense cloud of interplanetary particles, with the entry of Meteorites of increasing size, which in massive numbers, are capable of altering the climate for a long time. This explanation, discussed below, includes the hypothesis of gigantic asteroid collisions in some of these 100,000-year cycles, but not all.
Today we are studying the appearance of noctuliscent clouds, a fact related by NASA to the brightness of floating asteroid dust in the upper atmosphere, which was mentioned for the first time in 1885. Before apparently it had never been reported. Noctuliscent clouds are bright blue in color, easy to identify.
Nocticent clouds over England on July 6, 2016. Space Weather Gallery
Today this nocturnal phenomenon has been declared on the rise, and the season in which it arises each year is increasingly anticipated, with more hours of duration per night.
Some comment that the noctuliscent clouds are a warning that the cloud of asteroid particles is in fact growing larger and larger, putting on the stage the Earth's 100,000-year cycle.
If it is thought that large asteroids can generate numerous additional debris, the Earth every 100,000 years enters a dramatic environmental period, which not only means a simple ice age that forces massive migrations. This is a different crisis than the one predicted by man-made global warming.
International scientific committees predict for the next decades or the next hundreds of years, massive destructive effects on terrestrial life and ocean life just from global warming, but little is said about the crisis caused by the increase in the dust cloud. of asteroids and meteorites.
It should be remembered that scholars of the mass extinction of species on Earth attribute “a drop in sea level and climate change” as the most frequently invoked causes. However, citing the David Raup study as an example, “new theories of collisions with extraterrestrial bodies are gaining adherents. in extinction ”. It is also understood that both glacial cooling and global warming produce important changes in the oceans.
On extinctions caused by stresses on Earth, Mr. Raup emphasizes that "they are not necessarily massive, and may only disrupt society by eliminating those organisms that are most susceptible."
Glacial cycle and asteroid cycle
Daniel Karner of the University of Berkeley, in his 2003 presentation, said that “the fundamental period of ice age cycles was found to be not 23,000 years (as had been previously proposed), but rather of about 100,000 years ”.
In turn, Richard A. Muller, from the Berkeley Physics Laboratory, and Gordon J. MacDonald, in their 1997 study, validated the 100,000-year periodicity by presenting curves of the climate spectrum, with a very narrow value. The authors, like Daniel Karner, when analyzing all the cycles of the Earth that could be involved - eccentricity, variation of the axis and inclination of the orbit - agreed that this should have "an astronomical origin".
On the other hand, for Muller and MacDonald, this periodicity of 100,000 years could potentially be attributed to the variation of the Earth's orbital inclination, since it shows a great coincidence to the glacial periods, as long as the inclination is considered compared to a invariable plane of the Solar System.
The authors suggest that a gradual change in Earth's inclination causes a gradual increase in meteorites and interplanetary dust, which would be responsible for the periodic cooling of the planet, however they considered it appropriate to validate or confirm it with experimental tests.
The image shows the variations of the tilt vector of the Earth's orbit. The slope i is specified based on the reference direction. The symbol ? is the azimuthal angle or angle of the ascending node (crossing or passing through the crossing point of the ecliptic or orbit of the Earth). In Figures A and C, the curve is based on measurements that relate the Earth to the zodiac or the ecliptic. yield misleading periods of 70,000 years. In Figures D and M, the motion is related to the invariant plane. Considering the total angular degree of the Solar System and the 100000 years result. (Muller)
Muller and MacDonald in turn discarded the suggestion linking the 100,000-year climate change to the Earth's eccentricity cycle or its linear precession equivalent. This had been mentioned by scientists who analyzed the so-called Milankovic Theory, published by the Serbian Milutin Milankovic (1879-1958), at the beginning of the 20th century.
On the reason why climatologists in the past had not considered the existence of the 100,000-year cycle of Earth's orbital inclination as a causative factor in glacial weather, the authors mentioned two possible reasons.
"Since Milankovitch's work, the implicit assumption has been that insolation was the driving force in climate cycles, and insolation is not directly affected by orbital tilt." In addition, the scientist adds, the 100,000-year cycle is not obvious if the natural reference plane of the Solar System is not considered, which he called the invariable plane.
In the following image Muller compares the two ways of observing the earth cycle according to the inclination of our planet. In one case, it results in 700,000 years, and in the second. 100,000 years. This may have caused confusion.
Helium 3 measured by Farley and Patterson serves to visualize the extraterrestrial dust spectrum between 269 and 445 thousand years. (Muller)
When the oscillation of the Earth is considered with an inclination considering the zodiac as a reference (curve A), the resulting cycle is 70 thousand years, but considering the invariable plane of the Solar System, indicated by the plane of orbit of Jupiter, the The result is 100,000 years, the same number of years as climate change.
Muller in turn published the curve of the accretion of extraterrestrial dust, that is, the level of increase of these particles, for the period from 269 to 445 ka, determined from the measurements of extraterrestrial Helium-3 in the deep sea, carried out by scientists Farley and Patterson.
Researchers Stephen Kortenkamp and Stanley Dermott, in 1998 analyzed the fact that every 100,000 years in the last 1.2 million years, the Earth faced a significant increase (by a factor of 2 to 3) in the number of particles of interplanetary dust, which many call the zodiacal cloud.
"Continued accumulation of large amounts of dust can lead to substantial changes in Earth's climate," the authors concluded. The researchers also suggested that these meteorite clouds would be responsible for periodic ice ages every 100,000 years.
"Large asteroid fragments of a kilometer in size could be disturbed in the asteroid belt, with the imminent crossing of the Earth before its gradual periodic orbit change", indicates their study.
According to Kortenkamp and Dermott, the impact of a larger number of asteroids would not always have occurred, but when it does, it is a stage for large extinctions.
Craters dated with the same date. (Aberdeen University)
Asteroids that hit the earth on the same date
If indeed asteroids fall every certain period more frequently, as the cloud of interplanetary particles also grows, there must be some cases studied.
One of the great extinctions that the Earth suffered, to which the disappearance of the dinosaurs is attributed, is related to the impact of an asteroid or comet that caused the Chicxulub crater, 66 million years ago in Mexico.
A long way off, another asteroid dated to the same date caused the Boltysh crater in Ukraine.
"We don't have a definitive explanation for that," commented geochemist and petrologist Matthias Meier of the ETH Zurich Institute when publishing his study in March 2017.
"One possible cause could be a collision between two fragments in the asteroid belt, forming debris that could then have quickly found its way to Earth," added the scientist.
Matthias Meier highlighted that 190 large craters are known. He analyzed 22 of them, but apart from the craters mentioned, most did not have correct dates, so he could not confirm a periodicity.
More about the 100,000 year cycle
According to the analysis of Kortenkamp and Dermott, on previous studies, the interplanetary particles found in deep-sea sediments corresponding to a period between 250,000 and 450,000 years ago reveal a flow of these increases (a factor of 2 to 3) every close to 100,000 years.
It also found that the extraterrestrial helium 3 in deep-sea sediments have a variability that increases every 100,000 years, but lags 50,000 years out of phase with the growth curve of the interplanetary particle flux. According to the study, this lagged increase would be related to climatic changes in ocean currents that probably redistributed the sediments.
Such redistributions would explain why the predictions of the interplanetary dust flux in the models do not match the measurements. This has made it difficult to validate some theories. What is clear is that the Earth seems to always follow a 100,000-year pattern.
The authors pointed out that “four planets in our Solar System orbit wrapped in a thin cloud of dust known as the zodiacal cloud”, and that in the case of our planet it has been seen that “each year it accumulates approximately 3 X 107 kilograms of particles of interplanetary dust from this cloud ”.
These particles. they explained, they are picked up by aircraft flying in the stratosphere and analyzed in laboratories.
Earth in the middle of the asteroid bands
The authors mentioned that in 1984, observations of the zodiacal cloud from the Infrared Astronomical Satellite (IRAS) revealed prominent bands of dust near the ecliptic - Earth's orbit - that were associated with the three most numerous asteroid families. : Eos, Themis, and Koronis.
"These three families of asteroids remain the most abundant sources of dust that are unequivocally linked to observations of the zodiacal cloud," they stated. In their paper, Kortenkamp and Dermott explained that asteroids contribute three-quarters of this interplanetary dust.
Analyzing the Muller and MacDonald study, the scientists stated that "testing their hypothesis requires an understanding of the structure of the dust bands."
The interplanetary dust has an origin from the asteroids of the so-called Asteroid Belt, which is located at a distance from the Sun of 3 Astronomical Units (1UA corresponds to the Sun-Earth distance). Its orbital plane corresponds to that of Jupiter, whose orbit is also considered the invariable basic orbital plane. As the particles of this dust get closer to the Sun they disintegrate. The orbits of many asteroids cross Earth's orbit between its closest point to the Sun and its farthest point.
In this scenario, Kortenkamp and Dermott place the Earth orbiting the Sun completely embedded within these dust bands of the different asteroid families. Fact confirmed by astronomers. At times, the spatial density of the dust in these particles is accentuated near the extremes and there are periods of the year when more meteorites fall.
Classification of asteroids, according to their orbits. (Wikimedia)
Gigantic asteroids looming
Small, medium and also gigantic asteroids orbit the Sun periodically passing through the orbit of the Earth. NASA classifies them as potentially dangerous astronomical objects, since at some point one of them must collide with our planet. Something that has always happened.
The danger is added to the fact that the orbit of the asteroids can change due to the effect of gravity when approaching the Sun, the Earth, the Moon or planets like Jupiter.
This means that a predicted trajectory for the future is subject to continuous change.
If Earth entered its 100,000-year period in which it will gradually experience more nearby meteorites or asteroids, a greater number of possible impacts can be anticipated. This is just a theory of course, put forward by scientists from prestigious universities.
Cover photo: The Earth submerged in a cloud of asteroids and interplanetary particles, is the scenario that is replicated every 100,000 years according to changes in the Earth's tilt. A scientific theory suggests that this would cause global cooling that is replicated periodically on the planet. Archive image (NASA)
The Epoch Times