3 Rules of sustainable development: Environmental - Economic - Sociopolitical

Our planet’s biosphere, our common home, is not as vast as it seems. The portion of the biosphere that is intimately linked to man’s survival is in fact quite small. In the oceans, it is only a kilometer deep, in the land only two meters in depth, and the ceiling is relatively low, since beyond 7,000 meters the air is unbreathable and the cold is unbearable.

With such a low ceiling and thin layer of breathable air, it becomes difficult to understand how there are still people who do not believe that human activities such as the burning of fossil fuels and other industrial activities have a harmful effect on our habitat.

The History of the Concept
With the industrial revolution, the mechanization of agriculture, the expansion of trade and globalization, the Western world, the developing countries and the poor countries, in this order, have experienced an unprecedented development at all levels: increased production, population increase, increased consumption, increased needs for energy, and increased means of transportation, especially planes and automobiles, to the point that each family in the richer countries owns more than one car. Sadly, pollution and the environmental deterioration have been the inevitable consequences of this unbalanced development.

Only our planet did not increase, and since it did not increase, the results of this too fast and haphazard growth soon appeared, especially because of the “use and throw away” philosophy that has been in force for several decades. The concept of recycling is recent, and has not yet entered the minds of many people, which is quite strange as we have said in the previous article about the cycles of water, nitrogen, carbon, oxygen etc. which showed that life on this planet has always depended on recycling finite amounts of elements.

Recycling has always been the philosophy of life on our planet, although its inhabitants have lived for a long time, and many will still do, according to the “use and throw away” thinking. Nowadays, it is cheaper, and less hassle, to buy new than to repair. But to which is it cheaper? To the economy or to the planet? What kind of toll do we place on our planet with this type of short-sighted ill-considered choice?

The idea of sustainable development emerged at the United Nations Conference on Environment and Development in Rio de Janeiro, in 1992. Initially, only the environmental impact on development was considered, that is, the capacity of our planet to sustain a given level of development without depleting its resources or jeopardizing the lives of the future generations. The other two pillars – economic and social – appeared later.

It is easy to know whether what we are doing is sustainable or not; we just need ask ourselves if we can continue doing this over and over again, forever? The first thing to inquire is the environment – does it compromise the environment for the next generation? Secondly, we need to ask if it is conducive to economic growth. And thirdly, if this economic benefit extends to all or only to selected few, and whether it promotes peace, justice and social stability.

What we have seen so far is that the wealth that some produce is proportional to the poverty they cause, in short, the more wealth, the more poverty. Furthermore, in relation to the environment, we have lived with the mentality of the mule that says “after I die if there is no more grass that grows on all the Earth, I don’t care for I no longer need it”.

Development seen solely as economic growth destroys the environment and causes deep social inequalities. For development to be sustainable, it has to be tridimensional, that is, the aspects of social justice and environmental protection should be just as important as economic growth.

The Real Situation
“Long before we exhaust the physical limits of our planet there will be grave social upheavals provoked by the great divide existing between the income of rich countries and poor countries.” III Report of the Club of Rome (1976)

For a bench to stand, it must have at least three legs; it cannot stand on one or two; this is the same with sustainable development. Capitalism has long inflated economic development without thinking of the other two and this has created a world where 1% of humanity has more wealth than the remaining 99%.

More concretely, one percent of the world population holds 54% of the world wealth and the rest of humanity only 46%. The difference is abysmal and even worse is that the gap between the rich and the poor continues to grow… The capitalism that has created the middle class is destroying it, even in the rich and developing countries.

Immigration – The “grave social upheavals provoked by the great divide between the income between rich countries and poor countries” advocated by the Club of Rome are already happening. To defend themselves, the rich have entrenched themselves behind thick walls, some in process of being constructed between US and Mexico, others in the form of natural barriers such as the Mediterranean Sea, preventing the Africans from entering Europe.

The poor are barred from entering the European fortress or into North America, or Japan or Australia. However, the highly qualified professionals, surgeons, football players, musicians, architects, and lawyers always have the doors open to them. To the poor countries we search for raw material at low cost, cheap labour, human trafficking for adoption (not all bad), but also for prostitution, organ trafficking etc. This leads us to the next issue – globalization.

Globalization – Through globalization, the Earth functions as a unit. The means of communication have removed the constraints of space and time. Today, we no longer get to know what happened in the recent past, we get to know while it is still happening.

But beyond the informational aspect, globalization is fundamentally economics and its leaders are less and less the states and more and more the multinational companies. In the continuing quest for cheap manual labour, which often involves child labour, the multinational brands and logos call for a lifestyle and form a global culture that little by little replaces the local culture.

Globalization per se would not be bad in fostering close communication among all peoples. Following the physical principle of the communicating vessels, when we connect an almost empty bucket of water to a full one, water flows from the bucket that has more to the one that has less, until equilibrium is reached between the two. In principle, through globalization we should reach equality between peoples.

The problem is that globalization is an invention of the rich to exploit the poor. The communication is made through valves which are devices that allow the movement to happen in only one direction. In this case, the movement occurs from the poor countries to the rich and not from the rich to the poor.

Atmospheric Contamination – The industrial civilization derived its energy mainly from non-renewable raw materials (fossil fuels, especially coal and oil). It used these raw materials without control, as if they were inexhaustible. Air pollution is increasing at an astonishing rate: it has doubled in a single decade. The Earth’s ability to sustain this contamination and avoid its harmful consequences is limited.

Industries and automobiles remove large amounts of oxygen from the air, and in return emit large quantities of carbon dioxide. As the result, we are breathing more and more rarified air that can cause diseases, namely cancer; it also raises the average temperature of the planet by increasing the greenhouse effect, thus trapping too much heat, not letting it escape into space. Our planet is heading towards a planet like Venus by the ever increasing amount of carbon dioxide.

From the point of view of biology, the human species is doomed to extinction if it persists in destroying its environment. Every organism that destroys the environment in which it lives, will end up destroying itself. Science affirms that in order to survive, it is not enough to cut the CO2 emissions by 20% or 60% by 2050, it is necessary to cut it by 90% by 2030.

The Problem of Water – In many countries, the lack of water is the main reason why people cannot get out of poverty. Around 3.4 million people, mostly children, die every year from diseases associated with the shortage of safe drinking water, inadequate sanitation and lack of hygiene. The waterborne diseases are the leading cause of death worldwide – 80% of all diseases in the world. It is predicted that by 2035 half of the world’s population is expected to live in conditions of “insecurity” in relation to the supply of drinkable water.

• “If the wars of this century were fought over oil, the wars of the next century will be fought over water.” Ismail Serageldin, World Bank vice president in 1995
•  “The next war in the Middle East will break out due to scarcity of water supply.” Muammar Gaddafi
• “The conditions are set for a century of conflicts over water.” The Economist

 The Plastic – We are not just talking about the tons of plastics found in the stomachs of whales, but the micro plastics coming from the microfibers that are part of our clothing are even worse. These come from the washing machines, go into the rivers and seas, and become part of fish diet which we later consume.

In addition to plastics, fish are no longer a healthy choice of food that they once were because of the levels of mercury present in the sea water continue to rise. The older the fish, the more mercury is absorbed into its system.

A Planet With Only Duties – No one defends the rights of the planet. The Earth has no rights, it only has the duty to feed us. If we don’t take good care of it, it cannot take care of us and sustain our life.

Deforestation – Livestock farming or monoculture, of soya beans for example, is causing desertification. The land used was rich only within the forest ecosystem; without trees, it is quickly depleted, and it becomes necessary to resort to chemical fertilizers so that some agriculture can be practiced.

Deforestation is proceeding at a rapid pace, without taking into account that growth or recovery is slow. We need the trees, not so much to produce oxygen, because the great majority of oxygen comes from the marine forests, but to absorb CO2.

Forest fires of criminal origin that occur systematically in Portugal, California, Australia, have killed hundreds of people year after year, in addition to emitting CO2 into the atmosphere and desertifying previously luscious leafy zones.

The ozone layer, or the blue gas that protects us from solar radiation, has decreased so much due to the use and misuse of aerosols that it is no longer good for health to sunbathe. The truth is that we need very much to be exposed to sunlight in order to synthesize vitamin D which is so important to our overall health.

Garbage – Our cities produce tons and tons of garbage every day. On one hand, there is an increasing public awareness to recycle household waste in large cities, and on the other, it is forbidden to recycle leftover food by feeding it to animals. As the result, a lot of food ends up in the trash, which is in itself contradictory to the new mentality of recycling.

Oil tanker accidents at sea ruin the ecosystems for many years. It takes a long time to clean them up. Crimes, like the deliberate blaze of oil wells during the Iraq war that lasted years, have ejected into the atmosphere billions of tons of CO2.

Not many years have passed since the beginning of space exploration and already the orbit of our planet is littered with orbital debris or space junk comprised of various old satellites that stopped functioning. Everyone is thinking of putting more and more satellites into orbit, but no one thinks of retrieving those that no longer work.

The Attitude of Denial – We are sweeping the problems under the carpet. We postpone finding answers to the problems we have at this moment which will only get worse in the future. The attitude in general is that of denial, of not wanting to see, of not taking responsibility for the present behaviours that will deny the future of the next generations. God forgives always, human beings only sometimes, but Mother Nature does not forgive nor forget. Someone once said that with respect to the poisoning of our planet it is like poisoning the placenta that feeds the child.

Greenpeace has stated that if all the inhabitants of the planet were to live like the citizens of the rich countries, consuming and wasting the resources of our planet, the Earth would sustain life for a meager 3 months and then would die, contaminated and depleted of resources. For the latter not to happen, it would take the resources of 10 planets like ours.

Sustainable development is based on the principle that a sustainable and viable economic development is possible without destroying the environment or compromising justice, the world peace, and the habitability of the planet for the future generations.  Sustainable development is one that harmonizes economic growth with the reality of the biosphere or the protection of the environment and the individual and social needs of all the peoples living on the planet, that is, with the social inclusion of all.

Protection of the Environment
Regarding air quality, which is the most burning ecological problem, carbon dioxide that the economy emits into the atmosphere should not exceed the amount that plants can absorb by photosynthesis. It is similar to the scenario that a person should not drink more alcohol than his liver can break down. Currently, we are not able to maintain this balance.

Environmental degradation causes problems of physical health, but on the other hand, this same degradation arises from the moral and social values of people who annihilate the preservation of the environment. Forty-six percent of the world population lives in cities. This is why it is necessary to improve the air quality in urban centers by building more green spaces in the middle of cities that can improve the air and trap dust particles.  The covering of roofs of homes with solar hot water and photovoltaic panels connected to the electrical grid would save a lot of energy when it is most needed: during the day.

The environmental impact analysis refers to the care to be taken when building a business. The impact it will have on the ecosystem, on plant and animal life, needs to be calculated and considered without compromise. There are more and more species of plants and animals that are disappearing from the face of the Earth, and what is scary is a future where plant and animal life will be reduced only to those produced by agriculture and domestic animals – the planet will have no wild animals because there will be no more forests as these will be occupied by man.

At the time of this of writing, it is becoming big news the dramatic decrease of insect population due to the abuse of chemicals in agriculture. The insects are the ones responsible for the pollination of agricultural plants; without them there is no agriculture.

Economic Growth
A company needs to be profitable for it to survive and continue to exist. The problem is to make profit at any cost. There are many so-called “healthy” economies that operate at the expense of the health of the human beings who sustain them. What will be more important: the health of the economy or the health of those who sustain the economy? Paraphrasing the Gospel, the economy was made for man and not man for the economy. A healthy economy based on the exploitation of those who maintain it through low wages, no holidays, with shifts of more than 8 hours, will sooner or later collapse, since companies cannot operate in this way for long.

In order for an economy to be healthy, it has to have a balance between births and deaths; it has to have enough young workers to replace those who achieve reform and subsidize their reforms – or that what is called solidarity between generations.

In the last 200 years, the world economy grew six times more than in the past, and in the rich countries ten times more. This economic growth occurred at the expense of coal, in the first phase of the industrial revolution, and of oil in the second. To save the Earth we should move immediately toward renewable energies. But if we move in this direction, the economy will cease to grow as it has done in the recent past. On the other hand, the rich countries’ mode of life is not sustainable because if all peoples were to live according to this model, the Earth would die shortly.

To care for the Earth and at the same time let the poor live with more dignity, there can be no economic growth in the rich countries. We would have to lower our standard of living, but since we are not doing this, we find mechanisms to ensure that the rich are always rich and the poor always poor. For this reason the sustainable development is a utopia, a chimera.

Social Inclusion
Sustainability should be sought locally by each company. It should look around itself and bring together all those whose lives are touched by the company: suppliers of raw material, producers, transporters and consumers of the products. All must be included, because they form a greater community. If one loses, all lose in the short or long term.

A company that cares about its workers, that shares its profits among them, and supports social causes, is a company esteemed by workers who are motivated, productive and work better – whoever runs for love does not tire. The explorer explores the Earth, if a company exploits both the environment and the workers, thinking solely of profit, it will end up losing both.

Politics play an important role in rewarding companies that are sustainable at all three levels and penalizing those that are not, because they pollute more, because they do not take care of their employees, etc. In this way, being sustainable becomes now fashionable, because there are financial incentives in place. This is one way that politics tries to influence the economy, so that the latter is not the only one driving the world. All business activity must be economically profitable, socially just, and environmentally sound.

At the company level, this seems to be relatively easy and doable. During the first industrial revolution, there were some businessmen who, in a personal capacity, applied these models and were called philanthropists. To extend these practices to the global level does not seem to be as easy. However, according to the slogan “Think globally and act locally”, sustainability must be sought by each and every company but not imposed in an ideological manner.

Seventeen Sustainable Development Objectives for 2030
These were the millennium goals. As they were not realized within that time frame, they became the goals for 2015; and as the deadline passed once again without achieving them, they are now the objectives for 2030. We will see if they will finally be reached that year, but it does not seem that we are heading in that direction, when several countries have already abandoned the agreements signed such as the one in Paris and others, without fulfilling them.

1. End poverty in all its forms, in all places;
2. End hunger, achieve food security, improve nutrition and promote sustainable agriculture;
3. Ensure a healthy life and promote the well-being for all, at all ages;
4. Guarantee inclusive and equitable quality education, and promote lifelong learning opportunities for all;
5. Achieve gender equality and empower all women and girls;
6. Guarantee availability and sustainable management of water and sanitation for all;
7. Guarantee access to cheap, reliable, sustainable and modern energy for all;
8. Promote sustained, inclusive and sustainable economic growth, full-time and productive employment and decent work for all;
9. Build resilient infrastructures, promote inclusive and sustainable industrialization, and foster innovation;
10. Reduce inequality between and within countries;
11. Make cities and human settlements inclusive, safe, resilient and sustainable;
12. Ensure sustainable consumption and production patterns;
13. Take urgent action to combat climate change and its impacts, recognizing that the UN Framework Convention on Climate Change (UNFCCC) is the principal international and intergovernmental forum to negotiate the global response to climate change;
14. Conserve and promote the sustainable use of oceans, seas and marine resources for sustainable development;
15. Protect, restore and promote the sustainable use of terrestrial ecosystems, sustainably manage forests, combat desertification, and halt and reverse land degradation and loss of biodiversity;
16. Promote peaceful and inclusive societies for sustainable development, proportionate access to justice for all and build effective, accountable and inclusive institutions at all levels;
17. Strengthen the implementation mechanisms and revitalize the global partnership for sustainable development.

Be Part of the Solution and Not Part of the Problem
“Water and air, the two essential fluids on which life depends, have become global trash cans.” Jacques Cousteau

The market produces everything we want, according to the law of supply and demand. This law places an enormous power in our hands: through our demand, we have the capacity to influence the supply of the market. As consumers we are not aware of this power, but the producers of goods acknowledge us, for this reason they say that the client is always right.

The economic system of our society has accustomed us to use and enjoy consumer goods without educating us of their acquisition – it does not tell us how these good are made, by whom, under what working conditions, with what resources, how far they travelled to reach us.

As consumers, by our choices, we send messages to the market – if we prefer a product with certain characteristics, the market will try to produce it; if we choose to buy products from companies that adopt conducts that respect their employees and the environment, the market will ipso facto orient itself in that direction.

Similarly, if we reject a product because it was produce against our values, travelled many kilometers to reach us, used cheap labour or, even worse, child labour, contaminated the environment, if we set it aside and stop buying it, the market will in turn cease to produce it; it is enough that the sales fall by a mere 5% for the market to reorient itself.

In addition to being aware in our daily lives and adopting good ecological habits in our personal lives – such as saving water in the shower, walking short distances instead of taking the car, recycling household waste, turning off excessive and unnecessary lights – the use of power that we have as consumers has immediate and lasting effects that contribute to sustainable development based on the protection of the environment and on economic growth where everyone wins.

Fr. Jorge Amaro, IMC

3 Types of Solid Matter: Mineral - Metal - Organic

After studying that matter appears in the universe in three different physical states – solid, liquid and gas – and that among all the matter and elements in the periodic table only water exists in nature in these three states, we now turn to the three types of solid matter existing on Earth. These are the mineral, metal and organic solid matter.

We can look at the history of mankind from the relationship it established with these materials over time. These materials shaped and deepened the life of human beings, created culture and raised civilizations and empires.

Human beings were first introduced to the minerals: the Stone Age was the time when man used minerals fundamentally to make tools needed for his activities. This Age is divided into three distinct periods: the Paleolithic, the Mesolithic, and the Neolithic. Then came the Metal Age which is also divided into three periods: the Copper, the Bronze and the Iron. In relation to the organic matter, humans invented agriculture, plant cultivation and pastoralism, the rearing and domestication of animals, which were used as food, working aids, transport and power.

The Organic Versus the Inorganic
In the beginning when God created the heavens and the earth, the earth was a formless void and darkness covered the face of the deep, while a wind from God swept over the face of the waters. Then God said, ‘Let there be light’; and there was light. And God saw that the light was good; and God separated the light from the darkness. God called the light Day, and the darkness he called Night. And there was evening and there was morning the first day.

And God said, ‘Let there be a dome in the midst of the waters, and let it separate the waters from the waters.’ So God made the dome and separated the waters that were under the dome from the waters that were above the dome. And it was so. God called the dome Sky. And there was evening and there was morning, the second day.

And God said, ‘Let the waters under the sky be gathered together into one place, and let the dry land appear.’ And it was so. God called the dry land Earth, and the waters that were gathered together he called Seas. And God saw that it was good. Then God said, ‘Let the earth put forth vegetation: plants yielding seed, and fruit trees of every kind on earth that bear fruit with the seed in it.’ And it was so. The earth brought forth vegetation: plants yielding seed of every kind, and trees of every kind bearing fruit with the seed in it. And God saw that it was good. And there was evening and there was morning, the third day. Genesis 1:1-13

Paraphrasing the book of Genesis, in the beginning, everything was inorganic, that is, organic matter is composed of at least two kinds of inorganic elements, three in the case of carbohydrates, and four or more depending on the complexity of the organic matter. The first, and the sine qua non condition for organic matter, is the presence of carbon atoms. The second is the presence of hydrogen atom, almost all organic compounds contain hydrogen but there are exceptions. We can say that carbon and hydrogen are the backbone of organic matter, and therefore, of life. Note that life in the account of creation in the book of Genesis appeared on the third day, in the form of plant life.

Inorganic molecules may contain hydrogen or carbon in their composition: water, for example, contains hydrogen, but is inorganic because it does not contain carbon. Carbon dioxide contains carbon but is not organic because it does not have hydrogen. Any molecule containing carbon and hydrogen is necessarily organic.

Inorganic molecules are smaller than organic, they are usually found outside of living beings, animals or plants, and do not have carbon as the main element. The fact that they are inorganic does not mean that they are not of great importance to life, take for instance the case of water, mineral salts and even some metals.

Minerals versus Metals
Concerning the differences between organic and inorganic matter, both minerals as well as metals are regarded as inorganic.

Minerals – are inorganic solid substances, and are formed naturally and spontaneously in nature, without human intervention. They may take the form of compounds or mixtures of various minerals or as one of the 118 elements in the periodic table occurring in its native form.

Minerals contain a characteristic internal structure and specific physical properties, a definite chemical composition and a crystalline structure, that is, the atoms of minerals are organized in orderly repetitive three-dimensional geometric forms. Currently, approximately 4000 minerals have been catalogued and the rate that geological studies are advancing, more and more minerals are being discovered, some of them even of extraterrestrial origin.

Metals – are solid matter with the exception of mercury which is liquid at room temperature, and they can be composites or alloys, such as stainless steel and brass, and even simple elements in the periodic table, where about 80% of the elements are classified as metals. They are hard, opaque or shiny, and are good electrical and thermal conductors. In general, they are malleable, meaning they can be hammered into thin sheet, or ductile meaning they can be drawn into wires. It is also possible to fuse them to make alloys or more defined shapes than being hammered into sheets.

Ninety-one of the 118 elements in the periodic table are metals; while the others are either non-metal or metalloid, that is, elements that have properties of both metal and non-metal.

When we say that we need magnesium or iron in our diet, this does not mean that we need to ingest the metal form of these compounds, but rather that we should consume certain foods that contain the salt of these metals. In nutrition, minerals are inorganic chemicals that we need to thrive, for tissue repair, for metabolism, and for carrying out other bodily functions.

Let us now study mineral, metal, and both organic and inorganic matter which are composed of many elements that are individually inorganic, but together they form the basis of life.

Minerals
As was mentioned earlier, minerals are inorganic solid matter that are formed naturally in nature, and they have a definitive chemical composition, as well as an internal crystalline structure. In minerals, the specific atoms are generally arranged in an ordered internal structure with an established chemical chain responsible for giving this mineral its physical properties.

It is made up of the same chemical composition throughout. The 4000 or so minerals identified, each has a unique set of physical properties, and are classified according to colour, streak, luster, cleavage, hardness, reaction to acids, the shape that it maintains when fractured, transparency, density and electrical properties. As to their nature, minerals are divided into two main groups: the silicates which make up more than 90% of the earth’s crust, and the non-silicates which are subdivided into carbonates, sulfides, oxides, sulfates, halides and phosphates, and native elements such as gold, silver, copper ores.

‘Organic’ Minerals
As we have already mentioned, all minerals have inorganic origin but some substances are better viewed as organic minerals. What I mean by this is that there are compounds or solid matter that appear to be minerals, like pearl and amber, but we know have organic origin.

Pearl is formed when a foreign body or irritant, like a parasite or a grain of sand, enters into an oyster, mussel or clam. In order to defend itself, the mollusk secretes a substance called nacre or mother of pearl, the same material that lines the inner walls of the shell. The mollusk wraps the irritant in layers of nacre, and in this way, gets rid of the problem and heals the wound made by the irritant. The pearl is basically a healed wound.

Amber, on the other hand, is of plant origin. It is fossilized resins produced millions of years ago by various types of trees that are now extinct.

Rocks
These are composed of two or more minerals and are classified based on the presence of the most abundant one. As far as the formation process is concerned, there are three main classes of rocks: igneous or magmatic, metamorphic and sedimentary. The earth’s crust is made up of 80% igneous or magmatic, 15% metamorphic and only 5% sedimentary rock.

Igneous or Magmatic Rocks – These are rocks that are formed from the cooling and hardening of magma or lava. They are therefore crystallized from a liquid, beneath the earth’s surface from magma or at the earth’s surface from lava. The rate of cooling of the melt determines the texture of the igneous rocks, with fast cooling yielding small fine-grained crystals while slow cooling allowing large crystals to form resulting in coarse-grained crystals. Lava cool quickly at earth’s surface while magma cool and crystallize slowly. For example, basalt is a fine-grained igneous rock which leads us to conclude that it is formed by rapid cooling of lava at the earth’s surface.

Metamorphic Rocks – These are rocks that formed from the physical or chemical alteration of other rocks, igneous or sedimentary or another older metamorphic rock, as the result of extreme pressure and heat. This means that all metamorphic processes involve solid state transformation of existing rock types in a process known as metamorphism, or “change in form”. In other words, the creation of a metamorphic rock requires that the transformation of the pre-existing rock has not undergone lithification (transformation into magma) or sedimentation (breaking rocks into particles).

Sedimentary Rocks – When rocks undergo erosive processes, such as from the action of water and wind that “shatter” them into small particles, sediments (like the sand on a beach) are formed. These sediments, in turn, are deposited in the lower relief zones and as they clump together they can form new rocks, called sedimentary rocks. For example, limestone that exists in the coastal regions are formed by the accumulation of shells, corals, and bodies and parts of dead aquatic organisms is simultaneously a sedimentary and organic rock.

Ore – Rocks have minerals and when these occur in large concentration they are called ores. Ores are mined for metals like iron, copper, or non-metals like talc. Ores are minerals containing metals that have great economic value, which justifies their extraction. Iron, for example, is taken from a mineral called hematite; therefore, hematite is the iron ore. Aluminum is extracted from an ore called bauxite, while lead is extracted from an ore called galena.

Does this mean that metals are minerals? Recalling the definition of mineral above, we know that it is any inorganic, solid, and naturally occurring compound that has a crystalline internal structure and a definite chemical formula. Now metals are indeed inorganic, solid, and most have crystalline structures; but do they occur naturally? There are metals like gold that can be called mineral and metal at the same time because they are found in nature in their metal form and not from a melted mineral.

The Stone Age
For their activities, human beings needed tools. The provenance and nature of these tools have been changing with a gradual increase in complexity over time. Not having yet discovered metal, humans began by making tools out of stone. The Stone Age is, therefore, the time where stones were used as the preferential tool, in addition to tools from animal bones and wood. This great period began two and a half million years ago, and lasted until the end of the second or last Ice Age, around 9600 BC. It is divided into three different periods: Paleolithic, Mesolithic and Neolithic.

Paleolithic – or Old Stone Age, is a period where humans survived exclusively from hunting and gathering of fruits and plants; they were nomads, going from place to place searching for food.

Mesolithic – this is a transition period, in which in addition to hunting and gathering vegetation, humans learned to fish; they were still nomads.

Neolithic – or New Stone Age, the great revolution of this period was the introduction of agriculture and animal husbandry.  Propelled by shortage of food, human intelligence replaced the gathering of fruits with agriculture and hunting with animal domestication and husbandry. The appearance of the first settlements started and humans ceased to be nomadic. This period lasted until 4000 BC.

The Nature of Metals
Unlike minerals, the internal crystalline structures of metals are less static: since the atoms of metals are in close proximity to one another, the outer electrons of the atoms have great mobility, being attracted simultaneously to the nuclei of neighbouring atoms. In this way, they are no longer tightly bonded to a specific atom, but are free to wander through the entire metal.

It is for this reason that metals are malleable and good conductors of heat and electricity. We need to recall when we talked about atom, that the electrons are the most active part of an atom, and that atoms are linked to one another via their electrons to form compounds.

The Characteristics of Metals
Conductivity – metals are by nature good thermal and electrical conductors.
Malleability – they are very malleable, especially when subjected to high temperatures.
Elasticity – they are susceptible to deformation or shape changing when subjected to external actions.
Ductility – this is the ability of metals to be stretched to form cables and wires.
Luster – in general, metals are not dull but can reflect light very well from their surface, and can be polished.

The periodic table of elements does not, so to speak, recognize minerals as it divides its 118 elements into metals, non-metals and metalloids. As already mentioned, metals are malleable and good thermal and electrical conductors. Non-metals, on the other hand, are poor conductors of heat and electricity, and are not easily bent, like carbon, nitrogen, phosphorus, oxygen, sulfur, selenium, fluorine, chlorine, bromine, iodine and astatine. Metalloids have both metallic and non-metallic properties, examples are boron, silicon, germanium, arsenic, antimony and tellurium.

Our Everyday Metals
Metals can be divided into ferrous metals like iron and steel, and non-ferrous metals like aluminum, copper, tin, nickel, brass and bronze.

Copper – it is used particularly in electrical equipment such as motors, circuits (cables, switches etc.). They are also coins made of copper.

Iron – it accounts for about 95% of the world’s metal production, and is widely used in cars, boats, and buildings due to its low cost and high strength. It is sometimes replaced by steel when a higher hardness and strength is required.

Zinc – it is used widely in the production of brass and due to its low cost, it was used for a long time to make bowls; it is still used to cover the roofs of rural homes in Africa, in place of straws.

Tin – it is principally used in alloys, such as bronze, the bell metal (copper and tin), phosphor bronze, soft solder and pewter. It is also essential in the production of glass, soaps, perfumes, paper, medicines and fungicides. The sheets wrapping chocolates or cigarettes, for example, also contain tin.

Aluminum – it is used in windows and in structures where the resistance of iron is not necessary, aluminum is used because it is lighter.

Nickel – it is widely used in the fabrication of coins.

The Metal Age
With the introduction of agriculture and animal husbandry, human beings became less dependent on nature, freer and more independent, thus  with more free time to think. The tools invented completely changed with the discovery of metals. The metals that were discovered defined three periods: Copper, Bronze, and Iron.

The Copper Age (3200 - 2300 BC) – possibly the first discovery of a metallic material occurred by chance, when the stones that used to contain bonfires contained copper oxide and were reduced to metal by the heat. This will be the beginning of the extraction in metallurgy, based essentially on empiricism and in the direct and personal transfer of knowledge. Since copper is not very hard, the first use of this metal was in ornaments.

The Bronze Age (2300 – 700 BC) – bronze is an alloy or a mixture of two metals, primarily of copper with tin. Both metals are not very hard and are very malleable, yet together they form bronze which is a hard metal. Because of its hardness, bronze was not used for ornaments, but rather in agriculture tools, domestic utensils, and for weapons.

The Iron Age (1200 BC) – lastly the Iron Age, a metal that is more common than the previous two, and the last one to be discovered. The Earth’s crust is composed of 5% iron. As we have said above, this is the metal most used by man, since its discovery until today. Hence we can say that we are still in the Iron Age.

Organic Matter
As we have seen, the boundary between organic and inorganic matter is not always very clear.

• In general, organic compounds are produced by living organisms, inorganic compounds are produced by nature or man-made.
• Inorganic compounds can form salts, organic compounds cannot.
• Organic compounds always contain carbon, inorganic compounds do not.
• Organic compounds contain hydrogen-carbon bonds, inorganic compounds do not.
• Inorganic compounds contain atoms of metal, organic compounds do not.

Soil Composition
The soil or land that covers most of the Earth’s surface, with the exception of rocky surface, is also composed of particles that belong to three different classification:

Sand particles – are the largest of the three types of soil particles. Sandy soil has up to 80% sand; this type of soil do not retain water and nutrients well, so it has a very low value for life.

Silt particles – are the next largest soil particles, they make up the sludge or sediments. Soils with high silt content are found along riverbanks and are the most fertile in the world.

Clay particles – are the smallest of the three soil types, hence retain water the best but run the risk of becoming waterlogged, making it difficult for plants to grow. Therefore both clay and sand particles are not very fertile.

Fertile Soil
In addition to the three types of particles that make up all kinds of soil, good soils that are fertile rely on water and air, that is, on moisture and aeration. The amount of sand that the soil contains allows for the presence of air, the sand particles separate the organic matter and the clay, making it possible for air to enter. The quantity of clay allows for the presence and retention of water.

The humus that all fertile soil must contain, results from decomposition of plant residues and animal carcasses by the action of microorganisms. Humus is, in fact, the final result of this decomposition and confers a high degree of fertility to a soil; we can conclude that life feeds on life. It is nature that recycles itself and it is life that is diversified. The ideal soil for agriculture, which human beings discovered in the Neolithic Period, should be made up of 45% minerals (sand, silt, clay), 25% water and 5% organic matter.

The Chemical Composition of the Human Body
The human body is formed by the interaction of the same elements that make up the universe; it is therefore a micro-universe in itself.

Present in large quantities
Hydrogen, carbon, nitrogen, oxygen – are the constituents of substances present in the body in large quantities (sugars, proteins, fats etc.). Among them, hydrogen and oxygen form water which is responsible for more than half of the mass of a human body.

Present in smaller quantity
Sodium – present in blood and in other bodily fluids.
Magnesium – plays an important role in muscle function and in calcium synthesis.
Phosphorus – present in phosphate which allows for energy storage.
Sulfur – participates in the composition of some proteins.
Chlorine – present in blood and other bodily fluids.
Potassium – present in blood and other bodily fluids.
Calcium – constituent of bones and teeth.

Present in trace quantities
Fluorine – is part of teeth enamel that prevents cavity formation.
Chromium – participates in sugar metabolism.
Manganese – participates in the metabolism of sugars, fats, and in bone formation.
Iron – a component of hemoglobin, a pigment that carries oxygen in the blood.
Cobalt – part of vitamin B12 composition, which helps keep the body’s nerve and blood cells healthy.
Copper – helps in the occurrence of some chemical reactions.
Zinc – necessary for normal growth.
Selenium – aids in digestion and assimilation of oils and fats.
Molybdenum – helps in the occurrence of some chemical reactions.
Iodine – important for proper thyroid function.

The body or matter of a living organism is a complex and mysterious combination of organic and inorganic materials; with each organic material being in itself composed of simpler inorganic elements. Some of these simpler inorganic elements, on their own, that is, without being part of organic compounds, are needed for life to exist and to process itself. Examples of these are water and oxygen.

Inorganic materials therefore concur twice to make life possible. First, they are part of the organic materials that form the matter or body of a living organism, and second, they facilitate, support and make possible the life of that living organism. So, inorganic matter not only make up the core of the body or matter of a living organism but they also, at the same time, facilitate, promote and create the environment where the living organism thrives.

Fr. Jorge Amaro, IMC

3 Constituents of the Earth's Biosphere: Atmosphere - Hydrosphere - Lithosphere

Viewed from space amidst other planets, our planet Earth stands out even from the distance because of its various colours, an indication of its diverse composition, which is unlike what is seen of the other terrestrial planets which tend to be in general monochromatic.

Earth’s most outstanding colour is blue, hence it has been nicknamed the blue planet. However, it is not the only blue planet in our solar system; Neptune is also blue, but not for the same reason that Earth is blue. Neptune appears uniformly blue because of the 1% methane in its atmosphere which absorbs the red end of the visible light spectrum, reflecting back the blue end of the spectrum thus making it appear blue to us.

The blue of the earth is due to the amount of water that the planet contains which covers about 70% of the earth’s surface. In addition to the blue, we can easily see the green of the forests, especially the Amazon, and the brown of the land, especially the Sahara Desert. The solid surface layer of the earth is called the lithosphere (“litos” means rock in Greek) which corresponds to 29% of the earth’s surface. Finally, we can also detect some white patches here and there, moving all over the planet. This indicates that the earth has an atmosphere, that is, it is surrounded by gas and water vapor present in the clouds.

The biosphere, the habitat or vital space of life, is the sum and interaction of these three spheres: atmosphere, hydrosphere, and lithosphere. However, beneath the surface of the earth, as indicated in the diagram above, there are three other elements called crust, mantle and core that have some influence on life, and remind us how Earth was before the appearance of life.

The Atmosphere
The earth’s atmosphere is a relatively thin gaseous envelope composed primarily of nitrogen (N2: 78%) and oxygen (O2: 21%), with small amounts of other gases such as water vapour (H2O) and carbon dioxide (CO2). In addition to water in vapour form, there are also clouds of liquid water and ice. 

Conventionally, it is understood that the atmosphere is about 480 kilometers thick although there is no definite upper limit. Its density decreases with altitude, becoming thinner and thinner until it merges with the outer space that surrounds all the planets. Ninety percent of the atmosphere, however, is within the first 30 kilometers from the earth’s surface.

The further we move away from the surface of the earth, the more we’ll notice the decrease in the air density and air pressure, and in the force of gravity. The decrease in temperature with altitude is seen in the first layer of the atmosphere (but follows a more complicated profile in the upper layers). Without being airborne, we can experience this even at the earth’s surface if we rise from the Dead Sea, the lowest point on the planet at 420 meters below sea level, or climb to Mount Everest the highest point on the planet at 8,848 km above sea level. The variation in temperature can be between positive 50 degrees Celsius on the shores of the Dead Sea to negative 50 on top of Mount Everest.

If Earth was the size of a soccer ball, the habitable layer would be as thin as a sheet of paper. At the altitude of 11 km, the temperature is at minus 50 degrees Celsius – furthermore, even though there is enough oxygen for the engines of an airplane to operate, there is not enough for a human being to live; this is why the climbers of Mount Everest must use supplemental oxygen.

The earth’s gravitational pull also decreases with altitude, but it does not disappear completely. It has an average value of 9.8 m/s2, being stronger at the poles because of the shorter distance to the center of the earth and weaker at the equator due to the equatorial bulge. An object must overcome this force in order to rise through the atmosphere. However, the decrease in gravity is not as drastic as we might think and it continues to be felt even beyond the atmosphere.

The International Space Station (ISS), for instance, orbits at an average altitude of 400 km, and at that height gravity is still almost 90% as strong as at the surface of the earth. Like an airplane, if it did not move at a certain speed in a straight line, it would end up falling to Earth. The extraordinary speed at which the ISS travels, at 27,600 km/hr, makes it counteract the earth’s gravitational force, giving the astronauts who live in it the experience of weightlessness or constant free fall. Therefore, the televised videos of the astronauts floating in air inside the ISS is not due to an absence of gravity as many think.  

The same force of gravity that keeps us anchored to Earth is what keeps the thin layer of air that envelops our planet from escaping into the outer space. Of the other terrestrial planets aside from Earth, only Venus has an atmosphere because it is only slightly smaller than Earth (95% of Earth’s diameter and 80% of Earth’s mass).

Both Mercury and Mars are too small for their gravitational force to maintain an atmosphere clinging to them. Atmosphere not only supplies us with the air we breathe but it also protects us from harmful ultraviolet radiation from the sun, keeps us warm by virtue of the greenhouse effect, and reduces the temperature extremes between night and day as seen in planets without an atmosphere.

The earth’s atmosphere can be divided into five layers based on its temperature profile with increasing altitude, starting from the earth’s surface:

• Troposphere (0 to 12 km) – It is here in the lowest part of the atmosphere that climate change occurs and temperature tends to decrease with altitude.
• Stratosphere (12 to 50 km) – It is here that the ozone layer that protects us from the harmful UV rays is found and causes temperature to rise with increasing altitude; it is in this layer that the airplanes fly to avoid climate disturbances.
• Mesosphere (50 to 80 km) – It is where most of the meteorites burn out when they enter the atmosphere. Temperatures drop with increasing altitude and the coldest place on Earth is found here with an average temperature of minus 85 C.
• Thermosphere (80 to 700 km) – Air in this layer is very rarefied, that is, thin and temperature gradually increases with height, from 200 C to 500 C reaching as high as 1500 C at the top region of this layer. Because the air is very thin the molecules with high energy are very far apart so that heat transfer would not be efficient and hence it would not feel as hot as 1500 C would feel on the surface of the Earth. It is analogous to sticking one’s hand rapidly in and out of a hot oven. The ISS orbits in this layer.
• Exosphere (700 to 10,000 km) – This is the layer where most of the earth’s satellites orbit; the air is even thinner than in the thermosphere so that atoms and molecules may travel hundreds of kilometers without colliding with one another. Temperature can range from 0 to over 1700 C, colder at night and much hotter during the day.

The Van Allen Belt
It is usually described as two donut-shaped variable zones high above the earth’s atmosphere comprised of highly energetic charged particles that have been captured and trapped by the earth’s magnetic field. The inner belt can typically be found between 6,000 to 12,000 km above the earth’s surface and the outer belt between 25,000 to 45,000 km.

They act like a shield that protects our atmosphere from damaging energetic charged particles from solar wind and cosmic rays. Although its existence was proved in 1958, it is only since 2012 that more detailed knowledge of these belts has been collected by the Van Allen probes sent out by NASA.  It is because of the high radiation in these belts that many people think that humans never left the earth’s low orbit and therefore never went to the moon.

The Hydrosphere
The hydrosphere is the total amount of free water found on the planet that is not contained or confined chemically or physically in the minerals of the earth’s crust or in the living beings, both plants and animals. In other words, water that is on the surface of the earth like oceans and ice caps, in the underground as in groundwater and wells, and in the air as cloud. The hydrosphere occupies most of the earth’s surface, more than 70% of the total area of the planet. The volume of the hydrosphere is about 1.4 billion cubic kilometers.

The oceans make up most of the hydrosphere, about 96.5% of its total volume. Considering this fact, our planet should have been called Water and not Earth. The oceans and the seas serve not only as water reservoirs but also as heat sinks as they control the energy regime on earth’s surface, producing the necessary conditions for life.

Almost 97.5% of the water in the world is saltwater while fresh water makes up only 2.5% and of this, 69% is retained in the glaciers, 30% in the fresh groundwater and only 0.3% is the freshwater that we can use found in lakes and rivers.

The Lithosphere
The interior of the earth is composed of three main layers: the crust, about 1% of the earth’s volume, thinner under the oceans than under the continents, the mantle, 84% of the earth’s volume and is divided into an upper and a lower layer, and the core, 15% of the total volume of the planet composed of an inner core and an outer core.

Lithosphere is therefore comprised of the relatively cool and rigid rock combination of the earth’s crust and the upper part of the upper mantle. Now, below the lithosphere the temperature is believed to be about 1000 C, resulting in a weak, less rigid zone which seems to be continuously moving. This motion creates stress in the rigid rock layers and forces the plates of the lithosphere to move against each other. The movement of the lithospheric plates is known as plate tectonics, and this motion manifests at the earth’s surface as earthquakes and continental drift.

The seven most important tectonic plates or huge slabs of lithosphere are: the African Plate, the Antarctic Plate, the Eurasian Plate, the Indo-Australian Plate, the North American Plate, the Pacific Plate and the South American Plate. The shifting or collision between these plates produces high mountains like the Himalayas, and causes volcanoes and earthquakes.

Continuing the journey to the center of the earth, we find below the mantle, the earth’s core which is separated into two layers. The outer core is comprised of liquid iron and nickel with temperature varying from 4,000 to 5,000 C, and is responsible for the earth’s magnetic field. Under the liquid outer core is a solid inner core about 70% the size of our moon composed mainly of iron and at 5,700 C is as hot as the surface of the sun.

It seems to be a contradiction that the solid iron inner core is surrounded by liquid iron and nickel at such an extreme temperature. This is because the pressure inside the planet is so great that the atoms are forced to concentrate near one another, as with matter in the solid state, and the extreme pressure does not allow dispersion that characterizes atoms in the liquid state.

The average distance to the centre of the earth at the equator is 6,731 km, with the crust being 35 km thick, the mantle 2,855 km, and the core 3,481 km. Although the core is thicker than the mantle, it actually forms only 15% of the earth’s volume, with the mantle occupying 84% and the crust a mere 1%.

The Biosphere
Biosphere is the combination of the three factors described above: the atmosphere, the hydrosphere and the lithosphere. These three factors interact with one another, allowing life. The area of this interaction is very small – the upper layers of the atmosphere, the bottom of the sea (hydrosphere) and the bowels of the Earth (lithosphere) are not part of this equation. Someone once said that if we were to compare Earth with an apple, the biosphere will correspond to its skin.

The biosphere has therefore about 10 km of altitude in the atmosphere, most of the clouds are formed between the 2,000 m and 6,000 m; about 1 km of depth in the oceans, with some exceptions. Beneath this depth, the environment is very dark and cold. On firm land, only first 2 meters in depth are fertile soil, favorable for agriculture. Below the two meters, organic matter is scarce.

The Five Main Biogeochemical Cycles of Life
It is within this very small zone, where the lithosphere, the atmosphere and the hydrosphere meet and form the biosphere, that life is possible. The elements that make up these three spaces interact through five fundamental cycles: the water cycle, the oxygen cycle, the carbon cycle, the sulfur cycle and the nitrogen cycle.

We could understand these cycles as inorganic matter that temporarily transforms or is assimilated by organic matter to favor or permit life and then returns to its inorganic state.

These cycles are carried out individually, but also in interdependency with each other, for the efficient maintenance of the ecosystem. Living beings need many chemical elements and these must be available at the right time, in the right quantity, and in the right concentration relative to one another. This is the essence and the importance of these biogeochemical cycles.

In the oceans there are unicellular algae that release a sulfide compound which oxidizes in the atmosphere, producing condensation nuclei that are needed in the formation of clouds that transport water and sulfur to the land.

The green plants, both on land and in the sea, use carbon dioxide with water and sunlight to produce sugar. A byproduct of this reaction is oxygen, and it is for this reason that we have free oxygen in the atmosphere. Here we see the interaction or interdependency of three different cycles: water, carbon and oxygen. Without this interaction life would not be possible. Without the carbon and the water cycle none of this would take place and life as we know it would not exist.

Life on Earth depends on a constant recycling of vital and non-vital elements. Nature has always recycled because the elements are always the same elements. The water that now forms our body may have already been at the bottom of the sea, on top of a cloud, in the trunk of a tree or even in the body of a dinosaur. Nature has always recycled; human beings are only now beginning to realize that they cannot continue to have the use and throw away mentality; that they have to recycle because this is crucial to the life of the planet.

The Water Cycle
The water cycle is the principal biogeochemical cycle. It happens by the process of evaporation of surface water (rivers, oceans, lakes, etc.) on planet Earth and also by the transpiration of living beings, both plants and animals.

This cycle begins with evaporation, the phenomenon that occurs when water vapor rises through the atmosphere forming clouds. When the clouds become saturated and upon reaching very high altitudes where it is cooler, condensation of the water back into the liquid form takes place, which will fall and return to the surface in the form of rain or snow. This cycle is known as the short water cycle.

The long water cycle is when water passes through the bodies of living beings before returning back to the environment. The water is absorbed from the soil by the roots of the plants, being used in photosynthesis or passed to other beings through the food chain. In this way, water will return to the atmosphere or to the earth through breathing, sweating, feces and urine.

The water cycle is extremely important for the maintenance of life on the planet. It is from this that climate change occurs, the development of living beings and the functioning of rivers, oceans and lakes.

The Nitrogen Cycle
Nitrogen is a very important element for living beings for it is part of the composition of the two organic molecules fundamental to life: proteins and nuclei acids. The nitrogen cycle is the process by which this element circulates through soil and plants, from the action or utilization of this element by living organisms.

The air we breathe is composed of 78% nitrogen in gaseous form, this being its largest reservoir. In addition to the atmosphere, it is also possible to find nitrogen in oceans, in organic matter and also in soil.

Although nitrogen is in the atmosphere, there are some bacteria that have the ability to fix nitrogen from the atmosphere into the soil, releasing it in the form of ammonia molecules. Other bacteria have the function of converting this ammonia molecule into nitrates, and it is in this form that plants absorb nitrogen from the soil through their roots. There are also bacteria that can fix nitrogen into the nodules of the roots of plants, especially in the legumes.

Plant-eating animals absorb nitrogen by feeding on these plants. The return of nitrogen into the atmosphere occurs through other bacteria known as denitrifiers which transform the soil nitrate into nitrogen gas that returns to the atmosphere, thus closing the nitrogen cycle.

The Oxygen Cycle
Oxygen is an element present in diverse chemical compositions essential for the maintenance of life, such as in carbon dioxide (CO2) and water (H2O), which makes it possible for photosynthesis to take place in plants. In addition, it is an element necessary for human respiration, that is, indispensable for our survival.

The oxygen cycle is linked to these two phenomena: photosynthesis and respiration. In the process of photosynthesis plants and algae use carbon dioxide, water and sunlight to produce energy for their growth, releasing oxygen as a waste product; we human beings take in oxygen by the process of respiration to produce energy releasing carbon dioxide as a waste product, this therefore means that respiration and photosynthesis go together.

The Carbon Cycle
Carbon is used by living beings as a raw material in the synthesis of organic compounds through photosynthesis. It is oxidized in the process of respiration resulting in the release of carbon dioxide into the environment. The CO2 contributes, as we have seen, to the planet’s thermal balance, by avoiding the loss of heat to space by trapping it in the atmosphere, keeping the Earth warm enough to sustain life. However, the decomposition and burning of fossil fuels (coal and oil) also release CO2 into the environment.

The increase in the atmospheric CO2 aggravates the greenhouse effect that can lead to the thawing of the polar icecaps, with consequent increase in sea level and flooding of coastal cities.

The Sulfur Cycle
Sulfur is a yellowish substance found in the soil, which burns easily. It enters into the production of sulfuric acid, a substance widely used in fertilizers, dyes and explosives (gunpowder, matchsticks, etc.). Sulfur is found in sedimentary rocks, volcanic rocks, coals, natural gas, etc.

Sulfur is essential to life, it is part of protein molecules vital to our body. About 140 g of sulfur can be found on an average in a human body. Nature recycles sulfur whenever an animal or plant dies. When they decompose and rot, substances known as sulfates combine with water and are absorbed by the roots of plants. Animals acquire sulfur by eating plants or other animals.

Conclusion
Life occurs in the biosphere which is comprised of three parts: atmosphere – hydrosphere – lithosphere. Each of these parts contains organic and inorganic elements that through complex physical and chemical processes react with each other and with the elements in the other two parts in an eternal and interdependent recycling motion. As Lavoisier very well observed, in Nature, nothing is lost, nothing is created, everything self transforms.

Fr. Jorge Amaro, IMC

3 Movements of The Earth: Revolution - Rotation - Oscillation

The Providential Position of Planet Earth Within the Galaxy and the Universe
To speak of these three movements so essential to life on our planet, we need to frame them not only within the solar system, as we have already done in speaking about the interaction between the sun, the Earth and the moon, but also within our galaxy, the Milky Way, which may well contain over 100 billion solar systems similar to ours. According to the observations made of the outer space by the Hubble telescope, there may be 100 billion galaxies in the universe but this number is likely to increase to 200 billion as telescope technology gets more advanced.

It is providential that Earth is a telluric or terrestrial planet in the context of the solar system where most of the planets are gaseous; it is also providential the position Earth occupies among the four terrestrial planets, third place between Venus and Mars, where it is not too far from the sun like Mars, a too cold planet, nor too close to the sun like Venus, the hottest planet in the solar system.

It is providential the magnitude of our planet. Earth at 6,371 km in diameter is only slightly bigger than Venus at 6,052 km. Venus has an atmosphere of gas composition similar to that of Earth before the emergence of life; but because Venus is too close to the sun, life forms were not able to develop.

Furthermore, if Earth was smaller, like Mercury at 2,440 km or like our moon, it would not have large enough force of gravity to develop an atmosphere. If it was 6 times larger, like Neptune at 24,622 km, it would be gaseous like this planet. On the other hand, even if it was only twice as large, life as we know it would not be possible: animals and plants with the same structure and mass would weigh twice as much and collapse under their own weight.

Finally, it is also providential the position of our solar system in relation to the center of our galaxy. Our solar system finds itself 27,000 light years from the center of our galaxy. The Milky Way has more than 200 billion stars and a diameter of 100,000 light years. In our galaxy, there are zones of habitability and zones of inhabitability. The zones of habitability forms a ring around the center of the galaxy, the inner circle being 13,000 light years from the center and the outer ring at 32,600 light years from the same center.

This is the zone where systems that contain planets capable of harboring some kind of life may appear. On one hand, in the regions beyond those of 32,600 light years from the center of the galaxy, the star metallicity is too low to permit formation of telluric planets like Earth. On the other hand, less than 13,000 light years from the center, the exposure to highly energetic winds, such as supernovas, would be very hostile to life. Within our galaxy, therefore, we are in a very privileged position.

The Orbits of the Planets are Spiral not Elliptical
According to what we were taught in school, stars are motionless, only planets move. For this reason, we have the concept that the sun is a fixed, static, motionless star while the Earth, as well as the other planets in the solar system, revolves around the sun in an elliptical orbit. However, this is not what really happens; the revolution of the planets around the sun is not elliptical but spiral.

The incredible truth is that the sun revolves around the center of the galaxy at a dizzying speed of 828,000 km/hr or 230 km/s, and takes 225 million years to complete a full orbit. It is therefore incorrect to say that the Earth and the other planets move around the sun. The truth is that the sun, in its orbit around the center of the galaxy, drags the planets along with it.

The movement the planets trace in both being dragged by the sun and orbiting around it is, of course, a spiral not elliptical, which would result if the sun was motionless. The spiral is therefore the geometric shape of motion – a combination of a circle and a line, two diametrically opposed ways of understanding time.

The Greeks understood time as a circle – spring, summer, fall, winter – from where the myth of the eternal return was born. The Jews, on the other hand, understood time as a line that comes from the past and passes through the present to head into the future. They have as a paradigm their epic of the exodus from Egypt: the past, represented by the slavery, which passes through the present sacrifice with the crossing of the desert towards the future, the Promised Land of freedom and progress.

The sun moves, and as the consequence the planets follow the sun, or rather, the sun drags with it the planets that revolve around it, tracing out a spiral. This geometric figure is very familiar to us because it is the shape of our galaxy, the Milky Way, the form of hurricanes and tornadoes, the shape of the propellers that move both the airplanes and the ships, the shape of the screws piercing into the wood or other objects, the geometric shape of our genetic code, the DNA, and even the way our hair grows on top of our head, it traces out the shape of the Milky Way.

The spiral is also the geometric figure that water forms on its path down the drain in a sink or toilet bowl; this whirlwind rotates counterclockwise in the northern hemisphere and clockwise in the southern hemisphere, with no whirlwind at the equator. Even hurricanes and typhoons spin in spiral but in opposite directions according to the hemisphere in which they occur.

The Liturgical Year – Christian Concept of Time
The Christian concept of time is also a spiral that revolves around an axis that is Christ. As the Earth completes one revolution around the sun every 365 days, and so we complete a revolution around our Sun that is Christ, the axis of Salvation History: for “Jesus Christ is the same yesterday and today and forever.” (Hebrews 13:8)

I am the vine, you are the branches. Those who abide in me and I in them bear much fruit, because apart from me you can do nothing. (John 15:5)

As the Earth cannot live without the sun, we also cannot live without Christ, from him we receive life like branches from the vine stock. “Put on the Lord Jesus Christ, and make no provision for the flesh, to gratify its desires.” (Romans 13:14)

There is a Portuguese folk song that sings, “Spring goes back and forth, youth goes and does not come back”, which sums up the two ancient concepts of time into one. We live through the seasons again and again, and the seasons of the Church, such as Advent, Lent etc. again and again; but the spring or the Advent of last year is not the same as this year’s nor will it be the same as that of next year.

The rectilinear concept of time reveals that time is a continuous unrepeatable ongoing process – as the Greek philosopher Heraclitus said, we cannot bathe twice in the same river. The circular concept of time calls for constancy, the seasons repeat again and again; the spiral is the combination of the constant and the variable. Christ is the axis of History, He is the constant; the variable is each year around Him for the purpose, as St. Paul says, of putting on Him, that is, of us being more and more like Christ.

The Movement of Revolution of the Planets
Using the Earth’s year of 365 days (time taken for the planet to go one orbit around the sun) and Earth’s day of 24 hours (time taken for the planet to turn once around its own axis) as reference, here are the days and years it takes the other planets in the solar system, including our moon, to do these two types of revolution:

Mercury: a year lasts 88 days, a day lasts 58 days and 16 hours
Venus: a year lasts 225 days, a day lasts 243 days
Earth: a year lasts 365 days, a day lasts 24 hours
Moon: a year equals a day and both last 29.5 days
Mars: a year lasts 687 days, a day lasts 24 hours and 37 minutes
Jupiter: a year lasts 4330 days, a day lasts 9 hours and 56 minutes
Saturn: a year lasts 10,756 days, a day lasts 10 hours and 15 minutes
Uranus: a year lasts 30,687 days, a day lasts 12 hours and 14 minutes
Neptune: a year lasts 60,190 days, a day lasts 16 hours and 7 minutes

The Three Movements of the Earth
In school, we learn that the Earth has two movements, rotation around its axis taking 24 hours for a complete turn, and revolution around the sun taking 365 days which makes up one year with its 4 seasons which are more noticeable north of the Tropic of Cancer and south of the Tropic of Capricorn. However, Earth has yet one other less perceptible movement, but also cyclical that varies in the space of 26,000 years.

The Movement of Revolution
As we have said, the sun together with the Earth and the other planets of the solar system revolve around the center of our galaxy; but this movement does not affect us because it is a joint movement, that is, of the whole solar system in relation to the center of the galaxy.

What is more important is the movement of revolution that the Earth takes around the sun, as it is dragged by the sun’s gravitational force. Earth completes a turn around the sun in 365 days, 5 hours and 57 minutes, that is, 365.2422 days, the duration of one year, at a speed of 106,000 km/hr which is equivalent to travelling through space a distance of 2,544,000 kilometers every day. Why then do we not see the Earth move but rather the sun? For the simple reason that we are following this movement, just like when we are inside a moving car what we see moving is not the car but the trees that are still.

Going back to the traditional elliptical shape, for an easier understanding of this movement and its effects, the equinoxes (spring and autumn) correspond to the center of the ellipse and the solstices (summer and winter) to the poles of the ellipse.

The rotation of the Earth around its own axis alone does not explain the seasons of the year; these occur fundamentally because the Earth’s axis, an imaginary line that runs through the Earth’s north and south poles, is tilted 23.5 degrees relative to our orbital plane, that  is, the plane of Earth’s orbit around the sun. If the Earth’s axis was not tilted and hence it travels parallel to the sun’s axis, there would be no seasons and the climate would always be the same.

During the spring equinox (March 21), it is spring in the northern hemisphere and autumn in the southern hemisphere, and during the autumn equinox (September 23), it is autumn in the northern hemisphere and spring in the southern hemisphere. The word equinox is derived from Latin word aequinoctium to mean equal night, or when the day and the night have the same duration, that is, 12 hours of daylight and 12 hours of darkness. This occurs twice a year, on March 21 and September 23, when the sun’s rays fall directly on the Earth’s equator.

In relation to the sun, the tilting of the Earth makes no difference when it is halfway in its orbit around the sun. But during the solstices, when the Earth is at the apex of its elliptical path around the sun, it shows to the sun one hemisphere more than the other. On June 21, it shows the northern hemisphere so that the rays of the sun fall perpendicularly over this hemisphere. On December 22, the sun is on the other apex of the ellipse, so that it shows the southern hemisphere where it is summer and hides from the northern hemisphere where it is winter.

During the winter solstice (December 22), it is winter in the northern hemisphere and the summer in the southern hemisphere; the situation is reversed during the summer solstice (June 21) where it is summer in the northern hemisphere and winter in the southern hemisphere. During the solstices, the hemisphere that experiences summer is met with an increase in hours of daylight, while the hemisphere that is in winter experiences a decrease in hours of daylight. During the winter solstice, the North Pole is blanketed in darkness all day long and the South Pole has 24 hours of daylight; during the summer solstice, the situation is reversed and there is daylight at the North Pole all day long while the South Pole is plunged into complete darkness all day.

It is difficult to imagine the Earth without the four seasons, because they define its balance. In agriculture, there would be less variety of plants and animals, and certain viruses and pests would thrive to disastrous consequences, such as mosquitoes and the transmission of diseases they carry. Therefore, it would not only be the agriculture of the planet that would be affected, but also the health of the planet itself. Without the four seasons, the planet would always be cold on one side and hot on the other, not a flourishing scenario.

The Oscillation of the Earth’s Axis
The Earth’s axis is tilted 23.5 degrees; in this way, the Earth’s axis followed out into the space from the North Pole will point to a particular star and this star from the northern hemisphere is known as the North Star or the Pole Star. Presently the North Star is the star Polaris. But since the Earth’s axis also moves, the North Star will not always point to the star Polaris. As the axis moves like a wobbling spinning top, Earth traces out with its axis a circle that is completed every 26,000 years. It takes 72 years for the Earth to move one degree in this imaginary circle traced out by its axis.

The Polaris in the Ursa Minor constellation is today the North Star. In year 7500, it will be Alpha Cephei in the constellation of Cepheus; in year 11500, it will be Delta Cygni in the constellation of Cygnus; in year 14000, it will be the star Vega in the constellation of Lyra; in the year 23000, it will be star Thuban in the constellation of Draco; finally in the year 26000, the Pole Star or the North Star will again be Polaris in the constellation of Ursa Minor.

If the Earth’s axis was not tilted 23.5 degrees as it is, the perpendicular axis of the Earth, known as the north ecliptic pole would be pointed to the constellation of Draco, Latin for Dragon. For this reason, the center of the sphere that the axis of the Earth traces out every 26,000 years has this constellation at the center.

The Rotation of the Earth
The Earth rotates around its own axis (imaginary) and completes a turn every 24 hours. This counterclockwise movement is decelerating due to the influence of the moon on the Earth; that is, in the past, the days were shorter and in the future, the days will be longer. At the time of the dinosaurs, each day lasted 22 hours.

Why does the Earth spin around itself? To answer this question we must go all the way back to the Big Bang itself, the beginning of everything: time, space and movement. Everything that still moves in the universe today is the result of that initial movement, that is, from the big explosion. The Big Bang, as we know it, gave rise to a great cloud of hydrogen and dust.

As this cloud was not a homogeneous mass, as it expanded it provoked asymmetric gravitational forces that following the law of the conservation of angular momentum (it is more difficult to change the axis of rotation of a moving wheel than to change it when it is at rest) resulted in celestial bodies, both stars and planets, that are round.

Therefore, it is still the inertia of the first movement, from the great explosion, that keeps the stars and our Earth in particular rotating uninterrupted, until they are subjected to another movement, like an impact with another celestial body. Therefore, our planet was born already rotating around itself and it is logical that it will continue to do so while it exists.

Factors that Influence the Velocity of the Rotation
There are factors that influence the speed of rotation of the planets around themselves:

• The force of gravity of the sun – The closer a planet is to its star, the more noticeable this influence; while Mercury makes one complete turn around its axis, Earth would have already turned 58 times.
• The duration of the formation of the planet – The faster the gravitational collapse that formed a planet, the greater the conservation of angular momentum, that is, the greater its speed of rotation.
• The impact of meteorites – The impact of comets or meteorites, depending on their magnitude, disturbs the initial inertia of a planet and can decelerate or even project it out of its orbit.
• The influence of the moon – As we have already said, the moon decelerates the Earth’s rotational movement. The Earth loses its speed at a rate of one thousandth of a second per year. On the other hand, and by virtue of the effect the moon has on the tides, the moon is moving away from the Earth at a rate of one millimeter per year. In millions of years, each day will have 25 or 26 hours.

The Effects of the Earth’s Rotation
The most noticeable effect is of the day and night. If we embark on a spaceship and set ourselves hundreds of kilometers above the North Pole, we will see the Earth turning counterclockwise.

The rotational motion has a constant effect on the climate of our planet, that is, an effect that does not vary according to the seasons. This is known as the Coriolis effect: in the northern hemisphere the systems of low atmospheric pressure turn to the left and of the high pressure to the right; in the southern hemisphere the opposite is true.

The imperfect spherical shape that the Earth finds itself, somewhat flattened at the poles and bulging at the equator, is also a consequence of its rotational motion. For this reason, the flight paths that go from one side of the planet to the other pass through the poles and not through the equator.

The spinning movement favors or tones the magnetic field that surrounds the planet, and protects it from the sun’s rays and, above all, from the solar winds by diverting them to the poles, as we have already seen, giving rise to the auroras at the poles.

Finally, over time the fact that the Earth rotates around itself causes other changes or variations, such as the depth of the seas and oceans, the height of the mountains, and the movement of the tectonic plates.

We live on a planet that for billions of years has favored life, but is a living planet that is constantly changing, although imperceptible at times. Just as there was a time when there was no life on this planet, there may reach a time when it does not meet the necessary conditions to maintain life in the form we know it today.  For now, the fact that the Earth is the third planet in our solar system and has three different movements does not happen by chance, these are the requirements for life as the Trinitarian God of life has ordained it.

Fr. Jorge Amaro, IMC

3 Celestial Bodies of Life: Sun - Earth - Moon

The Origin of the Solar System
The Milky Way, the galaxy to which we belong, was formed around 13.6 billion years ago. Inside this galaxy, about 4 billion years ago, our solar system arose from a whirlwind of gas and dust, similar in appearance to a hurricane. The centre of this whirlwind became denser and denser until the sun was formed. The rest of the gas and dust formed the planets and other celestial bodies in our solar system.

Eight principal planets orbit around the sun, with their respective moons or satellites: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune; Pluto which was classified as a planet until 2006 was demoted because of its small size, which is about the size of our moon. Of these eight planets, the four closest to the sun (Mercury, Venus, Earth and Mars) are telluric or terrestrial, that is, they are composed of rocks and silicates, while the remaining four and larger planets are gaseous.

Mercury – In mythology Mercury means the messenger of gods. It is the planet closest to the sun hence its high temperatures, although part of it is dark and cold. Its surface is covered with craters. Galileo Galilei was the first scientist to observe it, in 1610. It is not the hottest planet in the solar system because, unlike Venus, it doesn’t have an atmosphere and therefore it readily dispels the heat it receives from the sun.

Venus – The god of love in mythology, Venus is the second planet in the solar system, and similar to Earth in size. However, it has no water nor any form of life. Its surface temperature can rise to 484 C, and is the hottest planet in our solar system.

Earth – Coinciding with our theme of tri-dimensionality of what is real, our planet Earth is indeed the third planet in our solar system, that is, it is in the best place for the appearance and sustenance of life – not too close to the sun like Venus and not too far away like Mars, even though these two other planets have almost the same dimension as Earth.

Mars – God of war in mythology, with low temperatures, Mars has two poles like those of Earth that can be seen during the Martian winters. This planet is well researched by space probes, which try to detect presence of life or to study the possibility of creating conditions conducive to life on the planet.

Jupiter – God of gods and father of other gods in mythology, it is formed by the same types of gas that make up the sun – hydrogen and helium. Jupiter is a giant gaseous planet, the largest in the solar system. If it was any bigger, it would be classified as a star, that is, it would burn like the sun.

Saturn – God of agriculture in mythology, it is the second largest planet after Jupiter. It is also gaseous, and has as its principal characteristic the rings that surround it, formed by particles of dust and ice.

Uranus – God of heavens in mythology, it is a planet that is so tilted on its axis that it undergoes its rapid rotation practically on its side. Contrary to the poles of the Earth, the poles of this planet face the sun. It has an atmosphere composed of hydrogen, helium and methane.

Neptune – God of sea in mythology, it is a large gaseous planet, and the farthest from the sun. It has some thick rings and some thin rings around it.

The Sun
I am the vine, you are the branches. Those who abide in me and I in them bear much fruit, because apart from me you can do nothing. (John 15:5)

Diameter:  1.4 million kilometers
Mass: 330 thousand times greater than the mass of planet Earth
Temperature: 15, 000, 000 Celsius at its core
The distance between the Sun and the Earth is approximately 150 million kilometers. Light takes about 8 minutes and 20 seconds to travel from the sun to us. The sun is a star of medium size and luminosity, there are billions of stars in our Milky Way galaxy that are much bigger than our sun.

The sun is composed primarily of hydrogen (74.9 %) and helium (23.8 %), its light and heat make it possible for living beings to survive on Earth. It is a nuclear fusion reactor: temperature and pressure at the sun’s core are such that hydrogen atoms fuse together to form helium atoms. This process releases a tremendous amount of energy which radiates to the sun’s surface, escaping into space as electromagnetic radiation of light and heat.

By its force of gravity, the sun pulls all the planets in the solar system to orbit around it. The law of gravity dictates that the body of the greatest mass attracts the bodies of lesser mass; for this reason all planets revolve around the sun from which they receive light and heat. Fortunately for life on Earth, our atmospheric layer blocks the sun’s x-rays, most of the harmful ultraviolet rays, and absorbs most of the infrared radiation. Were it not for this absorption, particularly of the x-rays and ultraviolet rays, the sun, the source of life, would have been the source of death…
 
Around every 11 years, the sun goes through a period of extreme turmoil, sending storms of charged particles to Earth resulting in our climate getting warmer and increased interference with magnetic instruments on the surface of the Earth. In addition to these electric discharges influencing the electronic systems on our planet, these waves of energy create the well-known Aurora Borealis and Australis, where the air shines in the regions near the magnetic poles of the Earth, generating in the sky a spectacle of lights and colours.

A solar cycle lasts an average of 11 years, and happens because there is a flip of the sun’s poles – north becomes south and south becomes north, and vice versa every 11 years. This flipping correlates with the minimums of sunspot activities, and decreased solar storms hitting the Earth, in other words, expected cooler climate. Interesting enough, we are at the end of solar cycle 24 and solar cycle 25 is expected to start sometimes in 2019.


The sun shines because it converts its hydrogen center into helium. This process creates the energy that nourishes us, but it also causes the sun to lose mass, that is, to become smaller and smaller. Every second that passes, the sun converts 600 million tons of matter into energy. Four and half billion years have already passed since this process started and the sun still have enough hydrogen to continue burning for another 5 billion years. After that the hydrogen will run out and our sun will die. Up until now the sun has already converted an amount of hydrogen comparable to 100 times the mass of Earth into helium and energy.
 
Contrary to logic, the sun is apparently not dying bits by bits, producing less and less energy. The more hydrogen that is converted into helium, the more the sun’s core shrinks, causing the outer layers of the sun to come closer to the center under a stronger gravitational force. This causes more pressure on the core, accelerating hydrogen fusion and increasing energy production, which leads to an increase of 1% in brightness every 100 million years. In the past 4.5 billion years, corresponding to the age of the sun, this energy has already increased by about 30%.

Consequently, within 1 billion years, the sun will be 10% brighter than it is now. This increase in luminosity will lead to an increase in heat and energy that the Earth and its atmosphere will have to absorb, causing in turn an increase in the greenhouse effect that little by little will convert our planet into what Venus is like today: the hottest planet in the solar system with temperature of about 500 C.

In 3.5 billion years, the sun will be 40% brighter than it is today. Under these conditions, the oceans will boil and water vapour will be lost to outer space, transforming our planet into a hot and dry planet like the present day Venus. At that time, it will not have temperatures higher than Venus, for the simple reason that Earth is further away from the sun.

When all the hydrogen in the sun’s core is used up, the inert helium ash, the result of the hydrogen fusion, will end up collapsing under its own weight. This will cause the sun’s core to become denser and hotter, causing the sun to grow in size and enter into its red giant phase.

In this phase of the sun’s evolution, the orbits of Mercury and Venus will be absorbed, two thirds of our sky will be occupied by the sun which will gradually encompass our planet. When it reaches this phase, the sun will still have 120 million years of active life. Finally, the accumulated helium will ignite violently and in the next 100 million years, it will burn the helium that resulted from hydrogen fusion.

The size of the sun will become ever larger until it turns into a white dwarf. In this state, it can still survive for another trillions of years to finally turn into a black hole.

The Moon
Equatorial Diameter: 3,474.8 km
Volume: 22,000,000,000 km³
Mass: 73,500,000,000,000,000,000 kg

The moon is the Earth’s only natural satellite and the fifth largest one in our solar system. It is also the largest in comparison to its corresponding planet. There are several theories to explain its formation. The one that gains most followers states that the moon came about from an impact of a celestial body the size of Mars against the Earth in the area now occupied by the Pacific Ocean.

The visible or the near side of the moon is characterized by large flat dark patches as viewed from Earth while the far side or the dark side of the moon, because it faces away from Earth, is rugged and has many craters formed possible from impacts with other celestial bodies. There is no atmosphere on the moon to protect any living beings from solar radiation; in other word, there are no gases at its surface like that found in the atmosphere of either Earth or Venus.

In addition to a lack of atmosphere, the moon also does not have water, which explains why it is devoid of wind (air) or hydraulic erosion (water). The average temperature on the moon is 106 C. In its revolution around the Earth, it goes through a phase cycle, depending on its position in relation to the Earth and the Sun. During this cycle, its appearance seems to change gradually from not being visible to being fully visible when viewed from points on Earth. The full cycle, that is, the lunar month lasts approximately 29.5 days.

The New Moon
The new moon occurs when the visible side of the moon does not receive any sunlight because these two celestial bodies have their axes pointed in the same direction. In this phase, the moon is in the sky during the day, rising at approximately 6:00 am and setting at 6:00 pm, like the sun. It is only at this phase that solar eclipse can be observed.

The First Quarter
During the subsequent days, the moon will move more and more to the east of the sun, and therefore the visible face will become more and more illuminated from the westward leading edge, until about one week later when we reach the first quarter phase, with 50% of the moon illuminated.

The Full Moon
During this phase 100% of the moon can be seen. The moon is in the sky all night, rising approximately at 6:00 pm when the sun goes down, and sets at sunrise, at approximately 6:00 am. The moon and the sun as seen from the Earth are in the opposite direction, separated by approximately 180 ° or 12 hours. It is only during this phase that lunar eclipse can be observed.

The Third Quarter
During the subsequent days after a full moon, portion of its illuminated face begins to become smaller and smaller, as the moon moves more and more west of the sun. The lunar disc will lose as the days go by a larger piece of its westward border. Until about seven days later, when the illuminated portion has been reduced to 50% and the moon is at its third quarter.

The moon is about 90 ° west of the sun, and is seen from the Earth as a semi-circle with the rounded part pointing to the east. It rises at midnight and sets at midday. In the days that follow, the moon continues to wane, until reaching the day zero of a new cycle.

The Hidden Side of the Moon
This is the side of the moon that we never see, the side that faces away from the Earth, the hidden side or the far side. The full rotation of the moon on its axis and its complete orbit around the Earth take the same amount of time to complete because the moon is gravitationally locked to the Earth, this results in the moon always showing the same side to Earth while the other side is not visible from our planet: the hidden face of the moon.

Applying to the moon the same logic of what we know of Earth – in the sense that the Earth’s rotational movement defines the day and its orbit around the sun defines the year –with the moon, the time it takes the moon to complete a full rotation on its axis is the same amount of time it takes for the moon to complete its orbit around the Earth; what is a day for the moon is the same as one year, and one year equals one day. Both the day and the year is equivalent to 27.3 earthly days.

It is therefore not true what many people think to explain why the moon always shows the same face to us because it does not rotate on its axis like the Earth; it does have this rotational motion, but it is synchronized with that of the Earth, so that we end up seeing the same side of the moon.

The Effect on the Earth’s Axis
The gravitational force of the moon keeps the Earth in a stable equilibrium with a tilt on its axis of rotation of 23 degrees. This tilt stays unchanged; without the moon’s gravity locking the Earth, the latter would rotate in a less stable and more variable fashion.

The Earth is like a spinning top that spins on itself: as the top loses speed, it tilts and gyrates with its top axis drawing wider and wider circles. The moon, however, makes these circles not vary in size and to remain constant. This makes the seasons occur with regularity each year. Otherwise, there would a frequent disruption of the climate, the poles would change position and the climate would be extreme and unpredictable.

The Effects of Tides
Tides are changes in the sea level caused by the gravitational interference of the moon and the sun (the latter to a lesser degree due to its increased distance) on the Earth’s gravitational field.

Due to the rotation of the Earth and the rotation of the moon, these elevations propagate across the surface of the Earth, causing high tides every 12 hours and 25 minutes, and low tides between high tides. Tides also occur in the earth’s crust, raising the floor as much as 10 centimeters during a high tide.

The effect of the tides is reciprocated between the Earth and the moon. Because the Earth has a greater mass than the moon, it exerts a much greater tidal force on the moon. It is very likely that the synchronization between the periods of rotation and revolution of the moon occurred due to this tidal locking effect.

Unknown to many people, this implies that the interaction between these two co-orbiting celestial bodies causes the speed of the Earth’s rotation to decrease at a rate of 2 seconds every 100,000 years, or increasing the length of one day by 0.0016 second every century, and consequently the distance between the Earth and moon increases at a rate of 4 centimeters per year because of the conservation of angular momentum. This means that without the moon, the days on Earth would be shorter. It is the attraction that the moon exerts on the oceans that causes the Earth to rotate more slowly than it would otherwise.

The Apparent Size of the Moon and the Sun in the Sky
The diameter of the sun is around 1,400,000 km while the diameter of the moon is about 3,500 km. Therefore the sun’s diameter is around 400 times that of the moon. But the sun is also about 400 times farther from us than the moon. This amazing coincidence results in the fact that both the sun and the moon as seen from the Earth have the same apparent size. This is why the eclipse of the sun is possible, that is, it is possible for the moon to cover the sun completely as seen from the Earth because the moon being 400 times smaller than the sun also happens to be 400 times closer to the Earth than the sun.

The Earth
Earth is the third closest planet to the sun, it is the densest and the fifth largest of the eight planets in the solar system.
Equatorial Diameter: 12,756 km
Polar Diameter: 12,713 km
Volume: 1,083,000,000,000 km³
Mass: 6,000,000,000,000,000,000,000,000 kg

The Three Motions of the Earth
All the planets in the solar system with the exception of Earth have two motions: a spinning motion on its axis and an orbiting motion around the mother star, the sun. The duration of these movements varies according to their mass, the satellites that orbit around them, and their distance from the sun. Based on Earth’s time, Neptune, for example, has a day of 166 hours and a year that lasts over a century and a half. Meanwhile, Mercury completes its orbit round the sun in 88 days and therefore has a year much shorter than ours. However, it takes Mercury practically two months to spin once around its axis, in other words, one day on Mercury lasts about two months. In Venus, one day is practically the same as one year.

Earth like the other planets in the solar system is continuously in motion. However, unlike the other planets, Earth undergoes three types of motions. The orbiting movement around the sun, which determines the duration of a year; the spinning movement on its axis which takes 24 hours or one day to make one full turn, and the oscillation movement on its axis that causes the Earth to vary its angle as it revolves around the sun, giving rise to the seasons and the most varied climates.

The Atmosphere of the Telluric or Terrestrial Planets

Mercury – There is no atmosphere in Mercury.

Venus – It has a very dense atmosphere made up mostly of carbon dioxide (96%), nitrogen (3%), and traces of water and sulfur gas, with even smaller percentages of argon, xenon, neon, and helium. The atmospheric mass of Venus is over 90 times greater than Earth's, resulting in Venus having the strongest greenhouse effect than any other planets in our solar system. Beyond this thick layer near Venus’ surface, there are thick clouds made up mostly of sulfur dioxide and sulfuric acid, which gives Venus its yellowish appearance.   This nebulous structure is so thick and persistent that the sun and other stars cannot be seen from Venus; furthermore, the sulfur in the clouds is highly reflective of visible light so that during the day the yellowing light is dimmer than that of an overcast day on Earth with the surface temperature rising to more than 460 C.

Mars – Without the extreme temperatures and crushing pressures, Mars have a force of gravity lower than Earth’s and an average temperature similar to that of Antarctica, at -50 C. Mars’ atmosphere much like that of Venus is made up mostly of carbon dioxide (95.3%), nitrogen (2.7%), argon (1.7%) with traces of water. The remaining planets, being gaseous, do not differ much from one another in terms of mass and atmosphere, except for the rings around Saturn.

The Evolution of Earth’s Atmosphere
Earth formed from cosmic dust composed of silicates that began to agglomerate 4.6 billion years ago until reaching its actual size, about 150 million years ago. At that time, Earth was a rocky ball of fire and lava, and had no atmosphere. When it began to cool down, a solid crust formed which occasionally liquefied because of the intense and continuous volcanic activities.

The gases that the volcanoes released formed the Earth’s primitive atmosphere which was composed of 40% nitrogen, 30% carbon dioxide, 25% water vapour, 5% methane, with traces of ammonia. As it rose, the water vapour in the atmosphere condensed and fell in the form of rain. However, as it fell onto the burning ground, it evaporated again, this cyclical process continued for 100 million years, but led to the significant cooling down of the earth’s ground temperature.

When the land temperature reached below 100 º C, the boiling point of water, water started to accumulate in the lowest points of the planet’s surface. The greenhouse effect diminished and allowed the atmosphere to become more permeable to solar radiation, particularly the ultraviolet radiation. Furthermore, approximately 80% of the carbon dioxide present in the primitive atmosphere was fixed in the silicates of the earth’s crust, giving rise to limestone and thus reducing its presence in the atmosphere.

As the consequence of this action from the ultraviolet rays and the electrical discharges of lightning on the primitive atmosphere, as well as the heat from the volcanoes, organic matter was formed and accumulated in the primitive oceans. The first bacteria and blue-green algae – cyanobacteria – appeared with the ability to initiate photosynthetic activity: the absorption of carbon dioxide to form carbohydrates releasing the first molecules of oxygen (which took place about 2.4 billion years ago).

This continuous process progressively enriched the earth’s atmosphere for 1.5 million years, allowing the appearance of more complex oceanic organisms that used oxygen in respiration. Furthermore, the oxygen released from the water into the atmosphere upon being bombarded by the sun’s ultraviolet radiation formed ozone which gradually filtered out the dangerous rays of the sun allowing living beings, which until then only existed in the oceans, to colonize the land environment.

Two hundred million years ago, the Earth’s atmosphere reached its present composition:

Nitrogen 78.08 % -- The most abundant component of air and also the most important for life. Nitrogen is a key component in the molecules of amino acids, proteins, DNA and RNA. The latter two are the genetic materials that contain information that determines the hereditary characteristics that are passed down to offspring.

Oxygen 20.95% -- This gas appears in the atmosphere in a proportion of about 21%. Oxygen gas (O2) is indispensable for cellular respiration: when breathed in, it is carried to all the cells in the body via blood, and reacts with glucose (C6H12O6), producing water (H2O), carbon dioxide (CO2) and the energy required to carry out all bodily activities.

Plants produce oxygen during photosynthesis (a mechanism that is virtually the opposite of cellular respiration), releasing it into the atmosphere. In addition, oxygen is also the main oxidizer, that is, it “feeds” the process of combustion.

As we know it, life on our planet is linked to the appearance of oxygen and vice versa. Oxygen and life are entrapped in the egg and chick logic, one depending on the other not knowing which one came first.

Carbon dioxide 0.035% -- This gas is one of the by-products of cellular respiration, which is released into the environment. Plants use carbon dioxide in the process of photosynthesis, producing from it their reserve of carbohydrates.

One of the causes of the greenhouse effect is the excess of this gas in the atmosphere due to the burning of fossil fuels – fuels formed by the decomposition of organic matter (oil, coal and natural gas).

Water vapour – Arising from the evaporation of the waters in the oceans, rivers and lakes by the action of the solar heat. Its amount in the atmospheric air varies according to the temperature, the region of the planet, the season of the year, among other factors. Some phenomenon important to life are due to water vapour: the formation of clouds, rain and snow.

Life is not only composed of organic matter but also of inorganic matter such as water, oxygen, mineral salts such as sodium chloride, and metals such as iron. These inorganic elements facilitate chemical reactions of the organic compounds that are responsible for life. In an analogous way, life only occurs on Earth but it would not be possible without the facilitation of the Sun and the Moon.

So we come to the conclusion that the macro system responsible for life is Trinitarian, or tridimensional, since it is the close interaction between three celestial bodies -- the Sun, the Moon and the Earth --- that makes life possible and sustains it on our planet.

Fr. Jorge Amaro, IMC