Carbon atom, which composes nearly 0.2% of the earth’s crust, has a very special place among elements. All living beings are formed from carbon-based compounds. In addition, 94% percent of compounds—that is, more than 4 million—contain carbon atoms. Certain carbon compounds form nearly 18% of the matter in living beings. The rest is mostly water. These compounds are used as building blocks in cell formation. Only carbon has the ability of compounding with other elements in sufficient variety and complexities in order to carry out the main functions that life is based on. As carbon atoms easily form chains by making chemical bonds, no other element is given such a quality. These chains formed in a line can separate into branches and can connect to form rings. These rings are actually polygons formed by three, four, five, six, or more carbon atoms. Due to this quality, carbon is the element that forms the basis of many things from the foods we eat, to the clothes we wear, from the fuels we use, to the furniture we have.

The heat level that makes carbon compounds possible is between -20 and +120 0C. Carbon compounds begin freezing at -20 0C and they begin breaking at 120 0C. In space, where extreme heat and freezing cold exists, the only heat range that makes carbon compounds possible is found on earth and this is a very sensitive heat range. Temperatures in our neighboring planets give a better idea: as hot as 450 0C in Venus, and as cold as -53 0C in Mars. Under these temperatures, it is impossible for carbon element to form compounds and thus living beings. Therefore, the earth is the only planet created with the suitable conditions that make life possible.

Crystal structures of carbon atom

Particular repeating arrangement of atoms in three dimensional space to form a certain geometric shape is known as a crystal structure.

Different crystal structures of the same substance are named “allotrope.” Carbon has three different allotropes found in nature: amorphous carbon (coal), graphite, diamond. In addition to these, an artificially produced allotrope is fullerene.

Amorphous carbon (coal)

Amorphous structure is one without a definite crystal structure; that is, one where atoms take their places in free order. A mass of carbon atoms of amorphous structure is known as coal. After plants die, they undergo chemical transformation with the activities of microorganisms. If dead plants collect in a suitable wetland and are buried into the ground with a geological process, the carbon amount in their body increases and they begin transforming into coal. Types of coal are categorized according to the carbon percentage they contain. Geologically, this transformation process takes a period of 15 to 345 million years. Coal is one of the most commonly used forms of energy.

Graphite

In graphite, carbon atoms are found in a hexagonal crystal structure. These sheets, resembling the surface of a honeycomb, pile up and form graphite. As the sheets are not connected with firm bonds, they easily shift when some force is applied. This is why graphite is used for eliminating friction at machine industry. The black substance in pencils is graphite hardened by adding some clay. Graphite can resist very high temperatures. Therefore it is used within the steel industry and melting metals. In addition, it is a very good conductor of electricity. For this reason, the brushes of the electric engines in household machines such as a washing machine and a vacuum cleaner are made of graphite. In recent years, graphite has been used as heat shields of space shuttles.

Diamond

Diamond is the hardest natural substance we know. In spite of being a transparent substance and having no color of its own, it can be found in pastel colors such as yellow, brown, or even dim black, owing to being mixed with other minerals. Diamond is a perfect electric isolator and is the substance with highest heat conductivity. For this reason, it can be cut without being deformed. In diamond, carbon atoms are found in a pattern to form a cubical crystal structure. Extraordinary resistance of carbon-carbon bond and its hard and integrated structure prevents its reacting with other things around. It burns at a heat of 850 0C. In a piece of diamond, there can be other atoms that cause impurity and decrease the value. In good quality natural diamonds, there is only 1 alien atom versus 100,000 carbon atoms. In addition to jewelry, diamonds are widely used at industrial products such as drills, glass cutters and the like. 75-80 % of diamond production is used in this industry.

Formation of coal, graphite, or diamond from carbon

Carbon based organic compounds were buried underground as a result of movements by the earth’s crust millions of years ago. Physical and chemical changes occurred with those organic masses through heat and pressure. Gradually, water, carbon dioxide, oxygen, and—in the highest phases—hydrogen leaves these masses. This organic matter called “turba” (first transforms into lignite, then to sub bituminous coal, then to bituminous coal, and then to anthracite). If the conditions allow, it transforms into graphite. Coal is the first type of substance formed by carbon atoms on their journey to become diamond. As lower values of heat, pressure, and time suffice for coal formation, graphite requires much higher values. Diamond is formed in the mantle layer of the earth at about 150-200 depth. This valuable substance is later carried to the surface of the earth by volcanic rocks such as lamproite and kimberlite. In order for diamond to form, an atmospheric pressure of 50,000 atm, 2,400 0C of heat, and a period of 3 billion years are required. Without this immense pressure and long time, the substance to be formed by carbon will simply be graphite. It is possible to transform graphite into diamond artificially; however, according to calculations, a minimum pressure of 10,000 atm is required. In 1955, for the first time artificial diamond was obtained under 100,000 atm, 2,500 0C heat, and by using chrome as catalyzer. However, the pieces of diamond obtained were small and black, most of them did not classify as jewels. In another attempt made in 1962, graphite turned into diamond under 200,000 atm, 5,000 0C heat, without using any catalyzer.

The similarity between carbon and human beings

As carbon atoms’ properties change according to the crystal structure, people’s lifestyle and view of life depends on the community they live in and their position in that community. In order to become diamond, the highest level of its kind, a person needs to undergo hard conditions. If carbon atoms were to say, “this is more than we can bear, we prefer easier conditions,” then they can be nothing more than graphite. If the conditions for graphite are avoided as well, then one cannot go beyond the level of coal. Diamonds are kept in safes and worn in most important occasions and graphite has different kinds of practical use as an industrial material. As for coal, it ends up in fire. The situation of human beings in a way resembles carbon atoms. Every person is made of the same elements biologically. Their value will naturally be different, according to the processes they underwent and the behaviors they presented. Some show patience in the face of misfortune, put their sincere trust in God, and become the diamonds of humanity. Some others, whom we can compare to graphite, attain a desirable level even if they cannot become diamonds. Those who choose to assume the lowliest form are likely to face a similar fate with the coal.

References

• H. W. Kroto, J. R. Heath, S. C. O’Brien, R. F. Curl ve R. E. Smalley. 1985. “C60: Buckminsterfullerene.” Nature 318. DOI:10.1038/318162a0.
• L. Vlasov, D. Trifonov. 2005. 107 Stories about Chemistry, TUBÝTAK., Ankara.

Around 4–5 billion years ago (bya) my formation began from the remaining matter after the creation of the sun. In time, this matter accumulated and formed the small planetary objects (planetesimals) which were the earlier forms of future’s giant planets. Our collisions continued with the planetesimals that orbited the sun. As a result of these continuous collisions and bombardments, my surface temperature raised to almost 6,000oC. What I am trying to say is that I was an enormous globe consisting mainly of metallic substances that were melted in boiling lava and showered by thousands of meteoroids and comets. God the Creator has hidden many messages of mystery regarding the entire process I endeavored for humans to discover.

When I began to cool down, my surface hardened like a shell, and because I was not yet sufficiently protected by the gaseous shield known to us today as the atmosphere, my shell was destroyed by the ceaseless continuation of the meteoroid bombardment as soon as it began to form. This transformation continued for billions of years. At last when the invasion of the meteoroids began to ease, I started to mature and slowly began the process of cooling down.

4.4 billion years ago

The creation of pieces of land that looked somewhat different than the seven continents at the present began. They were just sections of land floating on my coat of crust. The formation of crust around my surface was subjected to rupture due to the high pressure caused by the intense heat deep down inside me. Over a period of time this crust, which separated into a number of huge fragments (plates), experienced various deformations that resulted in the formation of mountains. This is how the basins of the ocean and the contours of the continents began to emerge. This was the period during which new specimens of rock (granite) and the floor of the ocean (basaltic), consisting of rising magma, formed the core of the continents. Today scientists are studying the oldest granites (billions of years old) that have managed to survive natural disasters and destruction to discover how the first continents were actually formed.

Granite is the rock that forms the cores of the continents (cratons). Cratons are produced by the primary component of the oldest crust. Cratons are light enough to float on my coat of crust; they are a system created in a way that enables the development of continents. These cratons are found especially in central parts of Africa and also in South America, Australia, North America, and Scandinavia.

My surface is made up of integrated fragments called tectonic plates. Even though my crust was created by rock, it was created flexible enough to allow the plates to move a few centimeters every year caused by the intense heat from beneath my surface.

Continents

Ground movement and various changes have occurred over time due to the dynamic structure of the continents and plates attached to the mantle. Discoveries of exactly the same fossils and identical fresh water organisms in two completely different continents far from each other have proved this. The actual reason for the plate’s activity is that my core is much higher in temperature than my surface. The core deep inside me is around 5,500oC. The greater portion of this intense heat occurred in my early days as a result of the collisions and bombardments I faced, and the remaining is related to the disintegration of the radioactive elements which settled particularly in my mantle section. The heat waves which spread from my core were passed on to the next layer of the mantle. The heat melted a section of my mantle layer and magma forced my molten rocks to the surface. The molten rock, which fills the spaces between the cracked plates, enables new rock to develop, and then the plates separate from one another.

Around the same period of the formation of new rocks, my plates and the continents found on them separated. The formation of rocks deep within ocean continues the creation of the range of volcanic mountains even today. The range of under-water mountains continues for about 12,000 miles between the Antarctic and the North Pole and rises above sea level in some places.

The region called Iceland between the North American and Eurasian plates was formed as a result of an enormous volcanic eruption. This is one of the few places where the separation of the continents is clearly visible. The crevasse of Iceland, surrounded by the American plates on one side and the other European plates on the other, is around 3 miles in width. This crevasse is increasing with the formation of new rocks and is expanding the distance between America and Europe. Scientists say that the distance between the continents is increasing by around 1 inch every year, so within a hundred years the distance between America and Europe is expected to increase another 8 feet.

3.4 billion years ago

The main continents were forced together by movement of the tectonic plates forming new continents, and there are still remaining pieces of these continents inside the cratons of Australia and Africa.

2.7 billion years ago

My first super continent is still the ruling territory. But due to the power built up by heat emerging from my core, the tectonic plates are on the verge of separating this continent. Because of the heat from my core, the main land has separated and oceans were formed in my surface. Today these oceans do not exist on my surface anymore; but you can still find their pieces in the continents by a careful look.

1.1 billion years ago

The supercontinent called Rodinia, a continent which contains most of the earth’s landmass, was created. Seven hundred and fifty million years ago (mya), the heat from my core began to break down this supercontinent, and as a result Rodinia was destroyed and a new supercontinent called Pangaea, the origin of all the continents known in the present day, was created.

Two hundred million years later (or five hundred and sixty-five mya): I became acquainted with bacteria, funguses, poriferans (sponges), earthworms, mollusks, segmented worms, and arthropods.

During the time when these creatures lived on me, the climate was moderate. Major volcanic activities occurred during this period when most of the land was covered by shallow seas. The sudden outbreak of the thousands of species of living creatures during this period may seem amazing to you; in fact, this was actually the first period in which complex structural vertebrates were created.

495–435 million years ago

I first became associated with the red and green sea algae. This was also the period in which various fish and sea creatures were created. The enormous landmass of this period called Pangaea gave me a totally different appearance and had a huge impact on the climate. The reason for this was that a large section of the land was so distant from the sea. The climate of the inland regions was showing deep scale signs of change with every season-certain periods of the year were very hot and others considerably cold. During this time, the ocean did not have the effect on the climate like it does today. This is why the climates varied to such an extent. The change of climate played a huge role in the extinction of many species of that period and destroyed almost 90% of the living creatures.

Creation has continued at a distinct magnitude during the millions of years that have passed, and between 270–340 mya larger proportioned variations of vegetation were created. In a short space of time, this vegetation formed into giant trees that covered huge areas of land. The largest deposits of coal were created from the fossilization of these trees, an example of creation that would make your life a little easier in the years to follow.

On the other hand, the territories began to gather together close to the planes of the equator, and this vast land was covered with rain forests resembling the Amazon. These immense lands of greenery were the marshy forests that were home to extinct ferns and the first seeds of the various groups of plant life. The inhabitants of this intense vegetation were mainly insects, centipedes, and scorpions, but much larger than the ones we know today. The plants and forests disappeared suddenly at the end of this period, and towards the end of the same period when the vast lands of Pangaea began to take form, the glaciers expanded, the sea water receded, and the arid climate changed dramatically along with the forestry structure and vegetation. Then the creation of many new creatures occurred.

250 million years ago

The supercontinent Pangaea began to break up, and this separation caused the formation of Gondwana in the northern hemisphere and Eurasia in the south. Throughout the millions of years, South America began to recede from Africa while North America receded from Europe, resulting in the formation of the continents as we know them today. Australia drifted from the Antarctic continent and moved slowly towards more moderate climates. The evolution of the continents continued to form the huge canyons and valleys in America, and the vast range of mountains, including the Himalayas and the Alps. Between 225–190 mya mammals were created, and between 190–135 mya, birds and alga were created, followed in the next period by plantation seeds which almost completed my preparation as a suitable place for you all to live.

100 million years ago

The plan of the present day continents became apparent. Sometimes my land masses would collide in the regions where the plates joined and caused activity like the formation of the mountains. Without this plate movement, there would have been no mountains created on the planet. During this period, the various species of dinosaurs and reptiles became extinct for reasons unknown to humans. Throughout the following 100 million years, the creation of the most significant mountain ranges, like the Himalayas, occurred along with the continuing collisions of the continents. These plates continue to move 5–10 cm every year and still cause collisions today.

Today I am the proud owner of seven continents. Africa-Eurasia is an enormous supercontinent which houses Africa, Europe, and Asia. Beginning from the plateau of Siberia in Russia, it reaches as far as Africa, but Africa-Eurasia is not my only supercontinent. North and South America joined by Panama also have vast territories. If the Bering Strait that separates Russia and Alaska were to freeze, a person who set out from South America could walk as far as South Africa covering a total distance of 25,000 miles.

Although you are may not realize it, the activity of the continents continues today, and my existence that began billions of years ago will continue in the future until the time comes for me to die (you call this doomsday).

There is another aspect of the continental activity that affects you. This occurs in the form of disasters, for instance the earthquake, an event of nature which has occurred for millions of years. This activity of creation occurs as a result of the intersection of the plates, the collision of continents, or the ocean plates submerging beneath the continent. The tsunami disaster in Indonesia in 2004 was the result of a catastrophic movement of these plates.

The exceptionally lengthy process of my creation explains the transformations and progress I have experienced until I reached the condition suitable for the most precious and honorable of all creation: human beings. I hope that every moment and every aspect of the manifestation of science, wisdom, power, and willpower of my life story and creation will be a guide for you in the future and will encourage you to be even more curious about my end and to bow to our Almighty creator in respect of all He created.

After the sixth phase, the typical characteristic in the universe was a temperature that reached as high as 4,000 C. At that temperature space was not as dark as it is today, rather it gleamed brightly. As matter condensed into gases and cooled down as time passed, the density values increased and the planets that we know today started to form out of the increasingly solidifying matter. The universe, presumably, was still a homogeneous gas cloud of helium and hydrogen when it reached an age of 700,000 years. Yet, the universe did not become a single galaxy by collapsing on a single point; rather billions of galactic centers were created. So, what made the universe wait as a gas cloud in just that state? Why did it not collapse in on a single point?

While cosmology has been asking this question for years, Roger Penrose, a theoretical physicist and black hole expert, tried to compute the first creation power in one of his studies in 1973. Some tiny particles, smaller than a proton, were discovered. Those particles had been formed not by the collapse of the stars, but during the first creation after The Big Bang. Although those tiny black particles were far smaller than atoms, they behaved like black holes and swallowed everything they encountered. Yet it seems that they left their footprints as they passed. It seems as if hydrogen and helium clouds had gathered around those enormous attraction centers and the cores of billions of galaxies had thus formed. The universe was being shaped and was expanding from particles made up of a cosmic soup, a gas cloud. The Qur’an also relates the great transformation that took place in shaping the universe:

Have the unbelievers not beheld that the heavens and the earth were a solid mass, then We separated them; and of water We produced every living thing, will they not believe, then? (21:30)

From Dust and Gas Clouds to Cosmic Systems

Stars, like living beings, grow older and demise. They go through an infancy, then youth and adulthood. Some gas and dust clouds, known as Nebulas lie among galaxies. Nebulas are considered to be the raw material of stars. In our galaxy, the Milky Way, gas and dust clouds are mostly located on the spiral arms that extend outward. An impact, called a shock wave, causes interstellar matter to come together and condense into huge clouds and spheres in space. The clouds that condense during the first formation of stars are so thin that they do not even have gravitational effect. Due to this lack of gravity, it has not yet been fully understood how these gas and dust clouds came together and condensed.

A condensed cloud heats up due to the collisions within it; these collisions increase as the cloud is compressed in a process that lasts millions of years. These collisions cause the cloud to sparkle and gleam. Initially, some rays, such as infrared or radio waves, are emitted.

While the star forms, the outer crust collapses very slowly, whereas the central parts collapse at a much greater rate. As the cloud condenses farther, it emits more light and starts to shine inside the dark, dusty covering that surrounds it. This nuclear cooking-pot, which has a temperature of 10 million C at its core, sparkles. With the flaring of the star, a disk forms around the newly created center. Strong winds, triggered by the powerful hot gases that are emitted from the upper and lower surfaces of the disk, blow in opposite directions; they sweep away most of the original gas cloud that formerly impeded the visibility of the new star. Thus, the star begins to be visible through an ordinary telescope. The energy produced in the center of the star after it has been formed and reaches a certain age, impedes greater collapse. This energy provides the necessary pressure to block the collapse of matter and seeks a way to escape. Hence, the star reaches an equilibrium.

We cannot observe stars being born in interstellar gas clouds with normal telescopes. This is because the gases in space and within the dust clouds act like the particles in cigarette smoke and absorb the light. Thus, we see the clouds as dark silhouettes on the surface of the star. Formations of stars can only be observed through infrared telescopes. An infrared telescope was first placed on a satellite sent into orbit in 1983. That telescope discovered thousands of young stars hiding in the depths of interstellar clouds.

A condensed gas cloud needs to be of a certain size in order to become a star. If the gathering gas clouds are not large enough, a different situation occurs: a planet is born! The stars and planet systems that orbit the stars are formed in this way. While stars are being formed, the planets are made out of smaller gas clouds.

The Sun is a typical small star that is relatively very young. We can see stars in space that are up to a hundred times as large as the Sun, or ones that are one-tenth its size. When stars are compared to the Sun, the dimmer ones that have a surface temperature of only 3,000 C are at the bottom of the range, while ones similar to the Sun, with a surface temperature of 6,000 C, occupy the middle range. Stars that are much larger than the Sun have a surface temperature surpassing 30,000 C. Contrary to general thought, larger stars live shorter lives, because the denser and the hotter the core is, the more intense are the nuclear reactions that take place.

Thus, these stars have brighter surfaces. A massive star that uses more nuclear power is more likely to run out of fuel sooner. On the other hand, a smaller star that uses its fuel sparsely has a longer life, even though it has less fuel. We know that there is a simple relation between the temperature and the pressure of a gas. If we heat up a gas in an enclosed container, the pressure will increase; if we cool it down, the pressure will decrease. When you think of a star with a temperature reaching millions of degrees Celsius at its center, you can understand how great the pressure is there. We know that heat is being produced through nuclear reactions. Every star is under the influence of an attraction force that approximates and compresses the elements of the atoms it contains. As the mass of the star increases so does the attraction force. This inward force is balanced by the force of outward nuclear explosions. The most significant reaction that ensures the vitality and continuity of the star is the transformation of hydrogen into helium through fusion. Yet, while this happens, the fuel lessens and the reactor will fail to function properly. At this point, the force of the pressure keeping the star in a balance is endangered and the star begins to lose its long struggle against the attraction within its mass.

As stars lose their fuel, they are exposed to different “deaths,” in proportion to their mass. The number 1.44 is the coefficient related to the mass of the Sun. Stars with a mass of less than 1.44 times the mass of the Sun become black or white dwarves, whereas those with a mass of more than 1.44 times the mass of the Sun become supernovas, neutron stars, and eventually black holes. If the mass of a star is more than 1.44 times the mass of the Sun, it will not remain as a dwarf. Its inner temperature and density will increase and the fuel, in the form of iron, nickel, chrome and cobalt, will not be able to burn anymore. Temperature and pressure turn the electrons and protons into neutrons by adhering them to one another. The iron core becomes a huge ball with a diameter measuring 100 kilometers. At a critical temperature the star explodes, emitting a billion times its normal light intensity. This is a supernova explosion. With the explosion, a terrific shock wave and the flow of neutrino (an elementary particle with zero charge and zero mass) spreads. The materials produced in the explosion flow into space as gas clouds.

The Event of the Supernova and the World

As a matter of fact, at one time we were physically part of a star. That star was probably larger than the Sun and was formed right after the creation of the universe, namely in the first few hundred thousand years.

At those times, the universe was almost completely made up of hydrogen. The solar system and the earth had been formed of this element. Hydrogen was the beginning of everything, and whatever material was available in the universe had been derived from the hydrogen atom. Only after being processed in the nuclear furnace for billions of years did hydrogen turn into helium.

Consequently, the star’s life was over. As the fuel in the depots was running out, demise emerged on the horizon. It began in fits and starts, and then when the furnace was about to go out, the mass of the huge star collapsed in on itself. Having increased in size after the collapse, the pressure triggered new nuclear reactions. Thus, a series of elements, ranging from carbon to iron, came to be part of the body. Finally, the star gave its all with an enormous explosion that we call a supernova. A billion-year life ended in just a few seconds. Atom particles at the core of the star melted and turned into neutrons in just a few seconds, and the parts closer to surface were thrown into space at a speed of ten million kilometers per second. It was a magnificent moment in which billions of degrees of heat was produced and in which a great light, as bright as one billion suns, shone. Some of the elements that are heavier than iron were also created during that time.

Supernova means death to a star. The enormous energy once unleashed heats up the outer layers of the star so much that the way is paved for new fusion and energy-absorbing reactions to occur instead of energy-freeing ones. Not only iron, but also other heavy elements, such as gold, lead, and uranium are manufactured in this furnace. These elements are thrown into space together with pre-synthesized and lighter ones, like carbon and oxygen, and combine with the wreckages of other supernovas. During the succeeding millenniums, new star and planet generations are created.

For our planet, fantastic and extraordinary cosmic events, such as supernovas, have been the starting point for the existence of some elements, like oxygen, gold and silver, and ultimately for the creation of life. The sources of carbon and oxygen that are essential to life, the silver and gold rings that we wear on our fingers, the lead plates on our roofs, and the uranium that fuels our nuclear reactors are all results of the death throes of stars that died prior to the birth of the Sun.

As we have seen, a supernova explosion causes matter to move from one point to another. As a result of such explosions, many of the remnants of stars are spread over space and new stars or star systems are created by the accumulation of such remnants. The Sun and the planets in our solar system and surely those in our universe exist as the result of a very early supernova. In this immense universe which houses humanity, the transformation that matter undergoes, and the gradual advance toward a certain destination, all indicate that the Divine Knowledge, Power and Will are intermingled with His Compassion and Grace.

Cosmology is the study of the universe’s beginning, formation, and evolution. Humanity has devised many cosmological theories. For example, ancient Greeks thought the universe was composed of four elements: earth, wind, fire, and water. Now, despite several millennia of effort, modern cosmologists are even worse off.

About 60 years ago, Fritz Zwicky realized that clusters of galaxies consist mainly of matter in some non-luminous form, defined as matter that we cannot see with our telescopes. Now, after decades of accumulated observations, most astronomers believe that as much as 90 percent of this material may consist of objects or particles that cannot be seen. That is, most of the matter in the universe does not radiate light. Previously, people called this phenomenon missing matter. Contemporary researchers prefer dark matter, for it is the light, not the matter, that is missing.

In this article, I discuss evidence that proves the existence of dark matter, possible candidates for dark matter, and the importance of dark matter in understanding the universe’s beginning and end according to the Big Bang theory.

Obsering the invisible

As dark matter emits no electromagnetic radiation (e.g., light, radio waves, and X-rays), it cannot be seen by a telescope. However, we can infer its existence through its gravitational effects on luminous matter. The most obvious example of this is observed when looking at the rotation rates of galaxies. Using the resulting information, scientists can calculate the speeds of stars as they rotate around a galaxy’s center (orbital speeds) in two different ways. The first way is to look at the light coming from stars in different parts of a galaxy. Through a close study of that light’s properties, they can deduce how fast and in what direction (whether toward or away from us) that star is rotating. The second way is based upon gravitational physics. Given that we know how much matter the galaxy contains, we can calculate how fast stars must be orbiting around its center. By accounting for all of the galaxy’s luminous matter (e.g., stars, gas, and dust), astronomers can calculate the star’s orbital speeds.

But there is a problem here: The two results do not agree. The only way to account for this difference is to posit the existence of a large quantity of dark matter in the galaxies. To explain the astronomical observations, this dark matter must surround the galaxy in a large spherical distribution (known as a galactic halo).

Is the gravity of the galaxies seen in this image strong enough to contain the glowing hot gas? Superposed on an optical picture of a group of galaxies is an image taken in X-ray light. The X-ray picture shows confined hot gas highlighted in false red color and provides clear evidence that the gravity exerted in groups and clusters of galaxies exceeds all of the individual component galaxies combined. The extra gravity is attributed to dark matter, the nature and abundance of which is one of the biggest mysteries in astrophysics today. Credit: Richard Mushotzky (*)

Another effect, known as gravitational lensing, gives evidence for dark matter’s existence. This effect occurs when a massive object’s gravity bends the light that is passing by. For instance, when a cluster of galaxies blocks our view of another galaxy behind it, the cluster’s gravity warps the more distant galaxy’s light into rings or arcs, depending on the geometry involved. By observing these rings, one can calculate how much mass should be present inside the galaxy to produce this pattern. Such calculations confirm that clusters contain far more mass than the luminous matter suggests.

Image of the rich galaxy cluster Abell 2218, taken with the Hubble Space Telescope. This cluster shows evidence of multiple lensing images, as well as numerous strong and weak arcs. Using information about the arcs and multiple images allows astronomers to reconstruct the mass distribution, which then gives us knowledge about the distribution of dark matter. (*)

Dark matter defined

Understanding dark matter is a key to other important issues in cosmology, such as how much mass the universe contains, how galaxies formed, and whether or not the universe will expand forever.

The posited explanations for dark matter can be grouped into three main categories:

– Dark matter could be some kind of ordinary matter that emits or reflects too little radiation for our instruments to detect. Such objects are known as massive astrophysical compact halo objects (MACHOs) and may be ultrafaint stars, large or small black holes, cold gas, or dust scattered around the universe.

– Dark matter could consist of exotic, unfamiliar particles (i.e., different from such known particles as electrons, protons, and neutrons) that we have not figured out how to observe. These are known as weakly interacting massive particles (WIMPS). Despite the many theories about them, their existence remains unconfirmed. These exotic particles are thought to have very small masses (smaller than atoms), meaning that there would have to be a huge number of them to make up the missing matter. Thus, millions of WIMPs are passing through Earth and us. They interact with ordinary matter only by means of gravity. Since the interaction is very weak, it is difficult to detect them.

Our understanding of gravity needs a major revision–but most physicists do not consider this option seriously.

Dark matter and the universe

The search for dark matter is more than trying to explain discrepancies in galactic mass calculations, for it is closely related to how the universe was formed and will end.

The Big Bang theory, which tries to explain how the universe was formed, maintains that in the beginning, everything was compressed into a single point. Then, a great explosion resulted in the universe being formed. It is still expanding. This theory is based on the fact that all galaxies, when observed with telescopes, are moving away from each other. After this explosion, matter started clumping together to form the stars and galaxies we see today.

The picture shows mankind’s deepest, most detailed visible view of the universe provided by Hubble telescope. Representing a narrow keyhole view stretching to the visible horizon of the universe, the Hubble Deep Field image covers a speck of the sky only about the width of a dime 75 feet away. Though the field is a very small sample of the, it is considered representative of the typical distribution of galaxies in space, because the universe, statistically, looks largely the same in all directions. In this picture, Hubble uncovered a bewildering assortment of at least 1,500 galaxies at various stages of evolution. (*)

One problem with this theory is explaining how the stars and galaxies were formed. If matter initially was distributed evenly in all directions, what caused it to clump together in some regions and form stars and galaxies? Gravity alone cannot cause this in a smooth universe, and so something had to supply the initial gravity that allowed galaxies to form. Physicists suggest that dark matter WIMPs accomplished this task. Since WIMPs only affect ordinary matter gravitationally, physicists say this dark matter could be the seed of galactic formation.

According to the Big Bang theory, there are three possibilities for the universe’s future. In a closed universe, gravity is strong enough to stop the expansion eventually and pull everything back to a single point. In an open universe, gravity cannot stop the expansion and so it will continue forever. In a flat universe, there is just the right amount of mass so that gravity can stop the expansion but not pull it back into one point.

The amount of dark matter that exists is crucial to determining the universe’s fate, because the Big Bang theory posits that the amount of mass in the universe determines gravity’s strength and, by extension, whether the universe will be closed, open, or flat. To quantify this, scientists define a constant, called Omega, as the ratio of the universe’s density to some critical density. A flat universe is said to have an Omega of 1, meaning that its density is equal to that of the critical density. If the density is greater than 1, the universe is closed; if it is less than 1, is be open. Without dark matter, the universe’s observed density is between 0.01 and 0.1. Therefore we live in an open universe. If a lot of dark matter were present, the universe would be closed. If there were just the right amount present, it would be flat.

Conclusion

The discovery of dark matter could affect our view of our place in the universe. If its existence were proven, our world and its inhabitants would be made of something comprising an insignificant portion of the physical universe. This probably would not affect our daily life, but would create a new scientific paradigm. In this sense, the discovery of dark matter would be as revolutionary as finding of extraterrestrial life.

Footnotes

1. Herman, R. and S. L. Larson. Is Dark Matter Theory or Fact? Scientific American (15 June 1998).
2. Rubin, V. Dark Matter in the Universe. Scientific American (March 1998).

* http://www.nasa.gov

The Qur’anic descriptions and those in the Hadith are remarkable for their accuracy in relation to what is known about the subject now. But, what was known then? Until 1688, among Muslim as well as European scientists, the Aristotelian account dominated, no one daring to question it. The two theories in Aristotle’s time were: (a) the embryo is preformed as a miniature in either the male semen or the female secretion and then grows in the womb; and (b) the embryo is actually formed and created out of the menstrual blood. Aristotle favoured the second view, adding that male semen caused the menstrual blood to coagulate, like milk curdling into cheese. The Qur’anic description tells us, by contrast, that (a) the embryo is not pre-formed but grows in successive stages (71.13-14, 23.12-14,22.5); and (b) is formed equally of male and female fluids (76.2). The relevant ahadith re-state what is in the Qur’an. Interestingly, while exegetes of Qur’an and Hadith did not fall into error in their account, many Muslim scientists and doctors, under the spell of Aristotle, repeated Aristotle’s (incorrect) view. Thus, about 700 years after the Revelation, Ibn Hajar al-Asqalani commented: ‘Many of the anatomists claim that the semen of the male has no role in creation of the baby. Its role, they claim, is limited to curdling the menstrual blood… The saying of the Prophet denies what they say. The semen of the male actually participates equally to that of the female in formation of the embryo.’

The pre-formation theory lasted in Europe into the 18th century when it was believed that a full miniature existed either in the female ovum or in the male sperm, then simply got bigger in the womb. This theory was destroyed gradually and was no longer held in any form after 1900. Von Baer (1829-37), called the ‘father of embryology’, identified the human ovum. Subdivision of the egg, i.e. growth of the embryo in successive stages, was properly demonstrated and understood in 1839 by Schwann and Schleiden. And in 1875, Hertwig described the fertilization of an egg by a sperm. Then in 1883, Von Benden showed that male and female cells contribute the same number of chromosomes to the embryo.

However, not until this century, have a number of discoveries established how and when the sex of the embryo is determined; how and when the hones and musculature, the organs of sight and hearing, the nervous system, and so on, develop. It is rather more than remarkable, therefore, that in Qur’an and Hadith we should find unmistakably accurate and detailed references to these matters.

The earliest of the successive stages of embryo development is the nutfah, in turn distinguished as male and female nutfah (in modern terminology, gamete), the two being commingled to form the nutfat amshaj (zygote). The Qur’an clearly and explicitly states (75.3(t), 53.45-6, 59. 58-9) that the sex of the embryo is carried in the fluid ejaculated by the male (X or Y chromosome in the fertilizing sperm). Also, in the Qur’an s emphasis that growth is from a lucre drop of fluid, we find a clear pointer to the fact that the spermatozoa make up a mere 0.5% of the ejaculated fluid, in which tiny quantity are carried an average 2 to 300 million individual sperms.

The nutfat amshaj (zygote) develops into ‘alaqah (that which clings) which attaches itself to the uterine wall. The stunning precision of the term ‘alaqah for the detail of how the zygote attaches, implants and is nourished in the womb, is striking in Dr Albar’s account. (For even more on the detail, see Sikander Hussain ‘Al’Alaq: the mystery explored’, Ark Journal, London, 1986, pp. 31-6.) The ‘alaqah is transformed into mudghah (chewed lump), the somite(s) from which hones and muscles are subsequently differentiated. The mudghah stage includes also the pharyngeal arches (out of which face, ear and neck are formed) – the marked indentations give the embryo the look of a ‘chewed lump’. The Qur`an’s allusion (22.5) to mukhlaqa and ghairu mukhlaqa, formed and non- formed development of the mudghah, is now readily understood as the critical period of organogenesis, when the embryo is most susceptible to factors which can cause congenital malformations. The Qur’an says (2.259): kayfa nanshuzu-ha thumma naksu-ha tahma, ‘how We erect them (the bones) then enclothe them in flesh’. Nanshuzu-ha, here inadequately rendered ‘We erect them’ is as informative as any modern textbook description, for example ‘With time a number of needle-like spicules are formed which progressively radiate from the primary ossification centres towards the periphery.’

The pre-formational aspects of embryo development are now understood as hereditary characteristics contributed by parental genes. In the Qur’an (81). 17-19), the nutfah (male and female gametes) is said to carry these predetermined characteristics. There are several ahadith confirming this reading. One, in the Sahih of Muslim, explicitly mentions 4O -42 days after fertilization as the moment when the angel enters the womb and ‘gives the nutfah its shape and form, creates its hearing and visual apparatus, builds up the hones, the muscles and forms the skin. He then asks, 0 God, is it a boy or a girl, what is its livelihood and what will be its lifespan? God gives His answer and the angel writes all that will come. ‘The textbooks tell us that ‘In the sixth week of development the Primordial germ cells invade the genital ridges; if they fail to reach the ridges, the gonads do not develop..’ The site of formation of the gonads is indicated in Qur’an 86.5-9 as ‘between the backbone and the ribs’. This is exactly right. Once formed the gonads differentiate into either male and female and make their progress in the body accordingly. Blood and nerve supply and lymph drainage remain connected, even in the adult, to the area ‘between the backbone and the ribs’.

In this review only a few of the great many correspondences between the Quranic text or ahadith and current knowledge about human embryo development have been mentioned. What is the point of noting these? Almost all of these Qur’anic verses have as their general context a reminder of the resurrection. The re-creation of individual human life after death. We are confronted with the fact of life as a stunning miracle of the Mercy and Omnipotence of the Creator. Knowledge of the successive stages of growth from the near-nothing of a spot of bodily fluid cannot but create a sense of awe at the responsibility one carries for the miracle of one’s life. And one carries it hack to Him whose care initiated, ordained, proportioned and sustained our life – the contrasted human contribution being that drop of ‘lowly fluid’. Then, what – except perversity – could allow us to doubt that the Creator has concern for how we use our lives, or doubt that He can and will bring us again to life so that we may ourselves understand fully the worth of our intentions and actions? Also, these verses, urging a meditation upon the fact of life rather than upon the fact of death, educate a positive temperament, a positive attitude. Religious responsibility can be awakened by reflecting upon the wonder of birth, as much as by reflecting upon the mystery of death.

No textbook about human embryo development can inspire reflections of this kind. Of course, it is also of the utmost importance to know that the information in the Qur’an, given in words which are extraordinarily precise and yet remain generally intelligible, is accurate. Most non-Muslims do not believe that the Qur’an is the Book of God verbatim, as Muslims believe. In trying to make sense of the phenomenon – so copiously illustrated by Dr Albar from the field of human embryology – of how so much accurate knowledge is there in the Book, they may be led to question the assurance with which they hold to their non-belief.