THE ORIGIN OF ALL THAT EXISTS,, Humanity has always been deeply preoccupied with the origins of everything around us, from stones and animals to planets and stars, including our own existence. At the core of this curiosity lies the quest for the origin of the universe itself, the foundation of all existence. The universal concern for the nature and origin of the cosmos is evident in the cosmogonies found in virtually every civilization and culture studied by anthropology. These cosmogonies provide narratives detailing the beginnings of the world and the creation of humankind.

Let us unravel and surf through the ideas throughout ages to understand what the universe and its origin itself was to its inhabitants across history.

Flat-Earth Cosmologies:

The idea of many early civilizations

Ancient civilizations, including the Egyptians, Greeks, Chinese, Arabs, Incas, Mayas, and Tupi-Guaranis, lacked modern astronomy but developed cosmologies rooted in their physical and cultural realities. For many, the Earth and sky coexisted with the realms of the dead and gods. Often, these cosmologies reflect a flat Earth perception from everyday experience. The ancient Egyptians envisioned a flat island divided by a river, covered by an arched roof supported on four pillars, whereas the Hindu cosmologies, shared by Hindus, Brahmans, and Buddhists, featured a universe as an egg encased in seven concentric shells of different elements. Babylonians imagined a two-tiered universe connected by a cosmic staircase. Dependent on corn and rainfall, the Mayans believed their creator, initially alone with the sky and sea, eventually created people from corn and water. In the Judeo-Christian Old Testament, a mysterious firmament divided waters, with gates to the Abyss, Limbo, and the House of the Winds.

Geocentric Models:

Rise of geometric methods and systems of philosophical thought.

Roughly 2,400 years ago, the Greeks had already devised sophisticated geometric methods and systems of philosophical thought. It should be no surprise, therefore, that they also proposed a more sophisticated cosmology than that of the flat universe. Theirs was in fact spherical, with the Earth ringed by celestial bodies that kept predictable orbits, and all encased by a fixed starry sky. An initial version of the geocentric model was presented by Eudoxus of Cnidus (c.400 – 350 BC, a Greek astronomer and mathematician born in present-day Turkey), and was followed by successive modifications. One of its revisions was proposed by Aristotle (384-322 BC), who demonstrated that the Earth was a sphere. He arrived at this conclusion after observing the shadow cast during a lunar eclipse. He also calculated the size of the Earth – at 50% larger than it really is. Aristotle’s geocentric model consisted of 49 concentric spheres which he believed could account for the movements of all of the celestial bodies. The most external sphere was that of the fixed stars, which controlled the behaviour of the inner spheres. The starry sphere, in turn, was controlled by a supernatural mover (entity). The Greek geocentric model underwent further revisions. Eratosthenes (276-194 BC, Greek writer, born in present-day Libya) used an experimental method to measure the circumference of the Earth, which he overestimated by only 15%. Ptolemy (Claudius Ptolomeus, 2nd Century BC, Egyptian astronomer and geographer) revised Aristotle’s model by introducing epicycles, a model in which the planets swivel in smaller circles as they orbit the Earth.

THE HELIOCENTRIC MODEL:

The idea that the Sun is at the centre of the universe

The heliocentric theory, suggesting that the Sun is at the centre of the universe and the Earth revolves around it, was first introduced by Aristarchus of Samos (320-350 BC), a Greek mathematician and astronomer. Aristarchus developed this concept by estimating the sizes and distances of the Sun and the Moon. Despite its groundbreaking nature, Aristarchus's theory received minimal attention in its time. This lack of recognition can be attributed to its contradiction with Aristotle's widely esteemed geocentric theory and the general resistance to the idea of Earth's motion.

In 1510, the Polish astronomer Nicolaus Copernicus introduced his heliocentric model in the anonymously circulated work Commentariolus, later openly published in 1543 as De Revolutionibus Orbium Coelestium.This heliocentric model not only revolutionised astronomy but also had profound cultural implications, challenging the deeply ingrained Aristotelian geocentric perspective.Copernicus' heliocentric model eventually gained acceptance, leading to the question of why Aristarchus' similar model had not succeeded 2,000 years earlier. After Copernicus' publication, technological advancements, notably Tycho Brahe's precise measurements without telescopic aid, surpassed the Ptolemaic system. Brahe's assistant, Johannes Kepler, later used these measurements to establish laws of planetary motion, demonstrating that planets move in elliptical orbits with the Sun at one focus. This realisation significantly improved the congruency between theoretical calculations and measurements compared to the older system

The discovery of the galaxy:

The groundbreaking moment of human history

Advancements in optical, mechanical, and photographic technologies shattered the idea of a fixed star sphere by allowing scientists to measure vast distances to the nearest stars. This revelation led to a paradigm shift, suggesting that stars and the Sun share a common nature, each potentially capable of hosting a planetary system.

Immanuel Kant, known for his philosophical contributions, made an early and surprisingly accurate conception of the galaxy at the age of 26. He proposed that the solar system originated from the condensation of a gas disk and belongs to a larger structure we now call a "galaxy." Kant also identified observed nebulae as similar systems, coining the term "island universes." Wilhelm Herschel, an astronomer and musician, made crucial observational strides by building large telescopes capable of studying fainter celestial objects with greater precision. His work revealed that stars are both scattered and grouped into clusters, forming configurations observable to the naked eye, much like the Milky Way.

Mapping globular star clusters unveiled that our galaxy is approximately 90 thousand light-years in diameter, consisting of around 100 billion stars orbiting a common nucleus. This realisation extended to the understanding that countless similar formations, now generically referred to as galaxies, exist in the universe.

Looking at stars and galaxies allows us to glimpse into the past. For instance, the closest star outside our solar system, Alpha Centauri, is 4.3 light-years away, meaning the light we see today was emitted 4.3 years ago. Similarly, when observing our neighbouring galaxy Andromeda, we are witnessing it as it existed 2.4 million years ago. This underscores the profound temporal aspect of celestial observation, with many observed stars having ceased to exist aeons ago