I REMEMBER a young girl, in company of her parents visited my Planetarium, which is one of the three in Africa. When she saw how vast the universe is, something came to her mind. She turned to her mother and said: “Mummy, where is heaven”?

In reply, her mother said to her: “Ask your father”. She then asked the daddy innocently: “Where is heaven?” In reply, her father said: “Go and ask the Founder.” I am certain that she was enthralled by how beautiful and vast the universe is. She must have been told that heaven is promised to exceed the earth in beauty and was curious to know where heaven is.

Just like this young girl, most of us have all been plagued with questions about the universe. Some of us must have speculated and asked questions such as: how did the world start? When did our planet come into existence?

How wide is the universe? Are we the first occupants of planet earth? How old is planet earth? Will this world ever come to an end? If so, when and how? I will attempt to answer these questions in this and subsequent articles. I will also propose a question: Is man the apocalypse?

A glimpse at the galaxy: God is able to do exceedingly abundantly above all that we ask or think… Eph. 3:20. This passage reminds me of the universe. The universe is so unimaginably vast that everything associated with it is introduced by the word ‘big’: the big bang, the big rip, the big freeze, the big crunch and the big bounce.

These may not be familiar phrases to persons who are not conversant with astronomical physics and cosmetology. However, permit me to break these down into simpler terms. All the ‘bigs’ referred to above tell the story of the five ages of the universe, and the projecture into what may become of the earth.

One of the most widely accepted theory of the birth of earth, and of the galaxies is the big bang theory, projected to have happened some 13.8 billion years ago. The big bang presupposes that there was an initial state of nothingness. Then matter was squeezed into an infinitesimally small space and in an instant, exploded in every direction. This process was called cosmic inflation.

This expansion was carried far in every direction, gaining speed as it went further. The further these masses went, the more it cooled down, producing the hydrogen and helium gas. This is the first age of the universe, the Primordial era, and this lasted around one million years. These gases thereafter came together and the chemical processes led to the birth of the first stars.

These stars had strong gravitational pull, and they pulled huge rocks into their orbits. These were called planets. And the combination of a star and its planets became known as galaxies. From the evidence of the Hubble Space Telescope, there are billions of stars in the universe. A star is like our sun.

When we look up to the stars in the night sky, what we are looking at are billions of suns of other galaxies. The peculiar galaxy, however, for us, is the Milky Way Galaxy, which is where the earth is. This birth of the stars and the creation of the galaxies mark the transition from the primordial age to the stelliferous age of the universe.

We are not alone in the universe, but we have no other home: Initially, man thought they were alone in the universe, and also that the world was flat. There was a folklore about the creation of the earth, that the earth was filled with water. Then a great tortoise swam up, bringing earth out of the water, and it spread the earth as far as land is seen today.

Well, this confirms the ignorance of the past. Pythagoras was the first to come up with the concept of a spherical earth. This was built upon by Eratosthenes who calculated the circumference of the earth, and almost perfectly, I must add. However, it was Galileo, in 1609, who created his own version of the telescope that could see planets outside earth. And that they were all orbiting the sun.

It was from this time that the idea of exploring what is out there in the galaxy became man’s fantasy. On August 23, 1966, NASA’s Lunar Orbiter 1 took the first complete picture of the Earth from the moon’s orbit, and on July 20, 1969, man stepped out of earth to the moon for the first time.

In 1990, NASA launched the Hubble Space Telescope which was meant to take pictures of the galaxy, or in another word, show us what else is out there, and how vast the universe is. However, out of all the exoplanets that have been discovered so far, scientists are yet to find another planet that is able to sustain life as earth does.

So far, earth is that only planet that has the right proportion of surface water, temperature, energy, atmosphere and nutrient to effectively support living. The earth is located in what is called the ‘habitable zone’. That is: it is perfectly distanced from the host star, the sun, to allow water to remain on the planet’s surface and the right atmosphere for life to survive.

If the earth was just a little closer or a littler farther from the sun, life will not survive therein as it does now. Also, earth’s atmosphere has the right balance of energy and chemicals that produce carbohydrates and proteins which help organisms grow, as well as breathable air.

There could be other planets in other galaxies that share similar features with earth, however, until this day, none has been found. Science has tested guesses that the Stelliferous era is the only era that can sustain life as we know it. This is because this is the period when our star, the sun, will generate the energy needed to sustain its exoplanets.

Around five billion years from now, the sun will be old, and it will begin to die. This will lead to imbalance in the milky way galaxy, and everything will de-generate, marking the beginning of the degenerate era, and the beginning of the end of the universe, until darkness will once again envelop the universe.

This is in the Black Hole Era and the Dark era. Like all good things, this world will come to an end one day, but this will start in the next five billion years. This is a long time to give comfort to many who are scared of death. However, recent realities suggest that life on earth may not last that long.

‘Man’ today was not the first settlers on earth: Palaeontology (the scientific study of life that existed from 11,700 years into the past) has revealed that there were intelligent life forms that existed on earth from around 240 million to 66 million years ago. This evidence was further concretised by the fossil remains of creatures which are generally called dinosaurs.

At the time of their existence, earth’s land was together, and was referred to as the supercontinent of Pangaea, at a period which was known as the Triassic period. These creatures thrived and lived as the apex predators on earth, a position man gallantly holds today.

Fossil remains of these creatures are found in every continent, even Antarctica, and the earth’s land had been broken to what it is today due to convectional currents in the earth mantle. However, 66 million years ago, the narrative changed. By the Alvarez hypothesis, an asteroid, the size of a mountain slammed into earth.

This collision caused massive destruction, including a shock wave, heat pulse, wild fires, tsunamis, volcanic eruptions, lethal acid rains and earthquakes. The dust and grime the asteroid kicked up hovered in the air and rained back down as hot dust. This raised global temperatures for hours after the impact, and cooked alive, animals that were too large to seek shelter.

The dust particles, however, remained in the atmosphere for years. This blocked the sun for several years, causing what became known as nuclear winter. Many animals froze to death and plants went into extinction. History also has it that there was an early human settlement about 10,000 years ago. Archaeological remains in Tell Abu Hureyra, was proof that they were killed off by a second asteroid impact on earth.

This is deemed to have been the reason man became farmers. The impact was said to have grossly depleted the planet’s animal resources, causing the early men to transition into cultivation, instead of the initial hunting and gathering. All these are proof that cosmic-sized events have the ability to alter the living status of the planet, and that life on the planet can cease to exist, on one hand, and that the earth has the capacity to outlive current civilisations on the other. What then is the threat to life on earth in this age? Next week, I will examine the world of nuclear and chemical weapons.

Aare Afe Babalola