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WHY MOON IS IMPORTANT TO LIFE ON THE EARTH PLANET
Fernando Alcoforado*
Earth was formed about 4.6 billion years ago from the disk of gas and dust that formed
the Sun and the other bodies of the Solar System. The Moon, in turn, was formed about
100 million years after Earth after a violent impact on Earth from a body the size of Mars
called Theia. The huge impact tore off part of the Earth, which was then a magma sphere,
and put it into Earth orbit. The fragments that resulted from the clash between Earth and
Theia formed the Moon.
The newly created Earth-Moon system began to exert a mutual gravitational attraction.
Such an attraction has produced (and continues to produce) the dissipation of an enormous
amount of energy from the friction of the oceans with the seabed during the tides' comings
and goings. As a consequence of such dissipation, the Earth's rotation speed was reduced
from about 6 hours, which lasted the primitive Earth day without Moon until the current
24 hours. At present the Moon continues to slow the Earth's rotation at a rate of about 1.5
milliseconds per century. To compensate for this decrease in the speed of rotation of the
Earth, the lunar rotation energy needs to increase which produces a gradual distance from
the Moon to the Earth at a rate of about 3.82 centimeters each year (Stacey, F.D. Physics
of the Earth. New York: John Willey & Sons, 1969).
The distance from the Moon to the Earth is due to the friction between the surface of the
Earth and the huge body of water that is on it and, over time, the Earth rotates a little more
slowly on its axis. A kind of gravitational embrace joins the Earth and the Moon. Then,
as the motion of the Earth decreases, that of the Moon accelerates. Moreover, when
something in orbit accelerates, that acceleration pushes it out. For each action there is an
equal and opposite reaction. This is Newton's third law. The distance from the Moon
affects our planet in many ways. To begin with, as the Earth rotates more slowly, the days
get longer. They are longer by two milliseconds each century.
What would happen to the Earth if the Moon were continually moving away? It would be
catastrophic for the planet Earth because the days could be 48 times longer. During the
night, temperatures would kill everyone cold. Throughout the day, no one could stand the
heat. On the coast, there would be violent winds of 200 km / h. In terms of life there would
be almost nothing left Other than super-resistant bacteria and worms. All this shows how
Earth is dependent on this barren mineral ball we call the Moon. Just to give you an idea,
before the Moon began to orbit our planet, one day it would last anywhere from six to
eight hours. Since then, interaction with the Moon has been slowing the rotation of the
planet. By celestial mechanics, this happens as the Moon moves away.
More than 4 billion years ago, it is estimated that the Moon was only 25,000 kilometers
from Earth. Today, the distance is 15 times greater. With this spacing of the Moon relative
to Earth, the rotation speed of the planet has gradually diminished. In about 3 billion
years, the length of day had evolved to 18 hours. Following this trend, the 24-hour day
that prevails today will not last forever. The Moon will continue to distance itself now, at
a faster pace than before, at a rate of 3.8 centimeters per year. This process must continue
until the satellite is 560,000 kilometers away. When this occurs, the rotation of the Earth
will stabilize, the days will take 1,152 hours and life on the planet will be unfeasible. This
process will take at least 4 billion years to happen. Probably, in this chaotic scenario will
not have humans to witness it because in the next billion years, the Sun will be 10%
warmer enough to make any form of life on Earth be unfeasible.
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Many people wonder: what would happen if the Moon suddenly disappeared? At once
someone would say that we could enjoy the stars, the Milky Way, and other wonders of
the cosmos without being overshadowed by the lunar light. There would also be no solar
eclipses and lunar eclipses. In addition, all the romanticism and mystery associated with
our satellite, which inspired so many songs, poems, short stories, novels, and so many
artists would disappear, but, only that would happen if our satellite suddenly disappeared?
Of course not!
The main consequences of the sudden disappearance of the Moon would be: 1) the
disappearance of the phenomenon of the tides; 2) the end of the stability of the axis of
rotation of the Earth; 3) the end of many terrestrial species and plants; And, 4) drastic and
global climate changes due to the disappearance of the tides and the destabilization of the
axis of rotation of the Earth. The disappearance of the phenomenon of tides resulting from
the gravity of the Moon would lead to the weakening of ocean currents whose waters
would tend to stagnate. The margins of the seas would lose their system of drainage and
natural cleaning due to the advance and retreat of the waters. The oceanic water would
tend to redistribute, taking the course of the poles, and the level of the sea would rise in
the coasts. The consequence of all this would be a drastic change in the Earth's climate.
The end of the stability of the Earth's axis of rotation would occur with terrestrial
precession that would become slower without the Moon, as when a top begins to sway,
about to fall, and can vary its axis in a chaotic way between 0 and 90 degrees. The axis
of rotation of Earth is 23 degrees from the plane of its orbit caused by the orbital motion
of the Moon that is responsible for the existence of the seasons, as we know them. The
end of the stability of the axis of rotation of the Earth would result in climate change on
a global scale, which could produce summers with temperatures that would exceed 100
degrees, and winters with temperatures below minus 80 degrees. In the most extreme
case, the axis of rotation of the Earth could align directly in the direction of the Sun, which
would cause areas of the planet to be under permanent sunshine and others in permanent
obscurity. The gigantic thermal differences between one-half and the other of Earth would
cause extreme winds, with speeds of more than 300 kilometers per hour and other
dramatic meteorological phenomena.
The end of many species and terrestrial plants would occur with the disappearance of the
Moon that would also affect life on Earth. The most immediate effect would be the
disappearance of the Moon's own reflected sunlight, which would alter the biological
rhythms of many animal and plant species that have adapted and evolved under the cyclic
presence of the lunar light. Many species would need to adapt suddenly to the total
obscurity of moonless nights. The disappearance of the lunar tides would affect mainly
the species adapted to the currents and marine currents, such as those that live in the coasts
to which the flow of the tides takes the nutrients, or those that inhabit seas and oceans,
accustomed to the current patterns of the marine currents.
Drastic and global climate change, resulting from the disappearance of the tides and
destabilization of the axis of rotation of the Earth, would be the factors that would produce
the most terrible consequences on terrestrial life. The vital rhythms of all animal and plant
species would be altered by these climatic changes: migrations, the heat season,
hibernation, etc. Plant growth would also be affected by extreme thermal variations. Many
species would be unable to adapt, there would be massive extinction of plants and
animals. In the very extreme case where the Earth's axis of rotation pointed to the Sun,
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life on Earth as we know it would be impossible in either hemisphere, and would only be
feasible at the equator, between the arid and icy hemispheres of the planet.
* Fernando Alcoforado, 80, awarded the medal of Engineering Merit of the CONFEA / CREA System,
member of the Bahia Academy of Education, engineer and doctor in Territorial Planning and Regional
Development by the University of Barcelona, university professor and consultant in the areas of
strategic planning, business planning, regional planning and planning of energy systems, is author of the
books Globalização (Editora Nobel, São Paulo, 1997), De Collor a FHC- O Brasil e a Nova (Des)ordem
Mundial (Editora Nobel, São Paulo, 1998), Um Projeto para o Brasil (Editora Nobel, São Paulo, 2000), Os
condicionantes do desenvolvimento do Estado da Bahia (Tese de doutorado. Universidade de
Barcelona,http://www.tesisenred.net/handle/10803/1944, 2003), Globalização e Desenvolvimento (Editora
Nobel, São Paulo, 2006), Bahia- Desenvolvimento do Século XVI ao Século XX e Objetivos Estratégicos
na Era Contemporânea (EGBA, Salvador, 2008), The Necessary Conditions of the Economic and Social
Development- The Case of the State of Bahia (VDM Verlag Dr. Müller Aktiengesellschaft & Co. KG,
Saarbrücken, Germany, 2010), Aquecimento Global e Catástrofe Planetária (Viena- Editora e Gráfica,
Santa Cruz do Rio Pardo, São Paulo, 2010), Amazônia Sustentável- Para o progresso do Brasil e combate
ao aquecimento global (Viena- Editora e Gráfica, Santa Cruz do Rio Pardo, São Paulo, 2011), Os Fatores
Condicionantes do Desenvolvimento Econômico e Social (Editora CRV, Curitiba, 2012), Energia no Mundo
e no Brasil- Energia e Mudança Climática Catastrófica no Século XXI (Editora CRV, Curitiba, 2015), As
Grandes Revoluções Científicas, Econômicas e Sociais que Mudaram o Mundo (Editora CRV, Curitiba,
2016), A Invenção de um novo Brasil (Editora CRV, Curitiba, 2017), Esquerda x Direita e a sua
convergência (Associação Baiana de Imprensa, Salvador, 2018, em co-autoria) and Como inventar o futuro
para mudar o mundo (Editora CRV, Curitiba, 2019).