THE OLDEST SCIENCE IN THE WORLD: A WALK THROUGH TIME

The Universe and its mysteries have always puzzled mankind. Everyday we have discovered another piece of this puzzle. We do not have all the pieces of the puzzle, so putting it together is proving difficult.

That is what astronomers do. Help us figure out the mysteries of the universe and put this astronomical puzzle together.

For as long as humans have been able to, we’ve been looking up to the skies in awe. The night sky is mesmerising, mystical, drawing us nearer and leaving us wanting to know more. The vastness can put things into perspective and explain the biggest existential questions that most people have. What are we doing here? What is our purpose? What is out there? The word Astronomy is derived from the Greek word ‘astron’, meaning star and it literally translates to ‘law of the stars’.

It is widely agreed that astronomy is the oldest science in the world. We do have astronomy to thank for many significant inventions that have made life better and as convenient as it is now. Like clocks, calendars, Wi-Fi and many other important byproducts.

MEASURING TIME

Imagining a world without clocks, calendars and other ways to measure time is difficult. Life as we know it revolves around time. The first traces of time keeping date back to about 7000 years ago in the African deserts of Egypt, about 800km south of Cairo. The site, Nabta Playa, is a stone circle, similar but much older than Stonehenge.

It is believed that the people that built the structure did so to monitor the seasons. The region is known for having seasonal monsoons, which could affect their food supply. Citizens and farmers relied on the Nile River flooding, to nourish their crops.

Therefore, monitoring the seasons of the year, would have been vital. To know when to plant and/or harvest would have ultimately aided in their food security and survival.

A few thousands years after this, there is evidence that shows that astronomy and star-gazing started emerging across the world, in present day China, India, Egypt and many other regions. Their knowledge about the cosmos started to advance and many civilisations started recording their findings. China has a very rich and long astronomy history and is said to have been the first to be able to accurately predict eclipses.

According to NASA, the ancient Babylonians were actually the first to (somewhat) accurately develop a calendar. The 12 constellations of the Zodiac can also be attributed to them.

Their calendar was 12 months and based on the phases of the moon. The word ‘month’ is derived from the word ‘moon’, which is what a month was then, a lunar cycle of phases. The Aztecs were also not very far off. They developed two calendars, one annual calendar with 365 days and one 52 year calendar, which acted as a century.

RELIGION AND RITUALS

The Catholic Church played a vital role in astronomy, and the current calendar that is used world-wide today, the Gregorian calendar, is named after Pope Gregory XIII (1502-1585). By the 16th Century, the Julian calendar, proposed by Julius Ceaser, was off by approximately 14 days, throwing out the date of the spring equinox and subsequently Easter.

The Pope then tasked the Jesuit Priests, the academic order of the Catholic Church (many of whom were astronomers and scientists at the time), to find out why and fix it. On Friday, 25th October, 1582, the new calendar was adopted and is still in use today. The Church has a long history of being quite involved and even funded a lot of astronomy research. This could be because the skies play a big part in religion. Looking at Christianity, when Jesus Christ was born, a bright star led the Three Kings/Wise Men to his location.

There are many other examples of the important role that celestial bodies play in religion and rituals. One example is Ramaadan, the holiest month in the Islamic calendar year. The exact day that it commences is determined by the moon. Ancient humans also had many rituals and superstitions, sometimes believing that certain celestial events were harbingers or omens of some kind. At times, the good kind and other times the bad kind.

The Bayeux Tapestry of the 11th Century shows King Harold II and other Englishmen fearfully looking up at Halley’s Comet before the Battle of Hastings, where they were defeated. The ancient Greeks are said to have developed highly sophisticated methods to study Astronomy, which they treated as a branch of Mathematics.

However, Plato and Aristotle took a different approach, they were interested more in understanding the reasoning of the motions of the stars and other celestial bodies.

Ancient Greek Astronomers were also one of the first to calculate the Earth’s circumference fairly accurately. They did this by measuring the shadow cast of two objects at exactly the same time in two different locations.

Considering the distance between the two objects, they then calculated the circumference of the Earth to be about 46 250km, very close to the Earth’s actual circumference of 40075km.

CELESTIAL NAVIGATION

Before maps and way before GPS, sailing the high seas was not an easy feat. The skills you would have needed to navigate to your destination required an understanding of celestial bodies and this meant that Captains and Sailors of ships had to have a thorough understanding of the skies.

Celestial navigation is essentially using the moon, stars and the sun to determine your position and which direction you need to go in. Travelling and transportation by sea were popular during the Middle Ages and by the 12th Century the compass was

invented in China, but many still relied on the heavens to find their way. It is believed that seafarers believed this way was more reliable. To determine his ship’s location, Christopher Columbus used celestial navigation. He also used an Astrolabe, which is a tool that helps you measure latitude by determining the angle of the sun or a star.

A total of 58 navigational stars were also commonly used to calculate location, which was vital while travelling in unfamiliar seas. If you were in the Northern Hemisphere, you may also have used the North Star or Polaris, to determine where true North is. It is the only star in the night sky that does not move. This is because its position is almost directly above the North Pole.

MODERN ASTRONOMY

The ancient Greek astronomer Aristarchus of Samos is thought to have been the first person who suggested a heliocentric system, but there are not many descriptions of his idea that has survived. It was not until the 16th Century that this idea caught more steam. Before this, it was believed that Earth was at the centre of the universe.

Polish Astronomer, Nicolaus Copernicus, proposed the Heliocentric system. He said the Sun was at the centre of our solar system and that all planets, including Earth, orbit around it.

More important discoveries were to come with Galileo Galilei, but not everyone was on board. The Catholic Church banned his book and told him to denounce the Copernican theory of the Heliocentric system. Galileo also built his own Telescopes and some say popularised their use. He is one of the most notable and recognisable names in Science and Astronomy. In 1744 the Catholic Church unbanned his book Dialogue and in 1992 the Vatican formally apologised for condemning him. George Lemaitre (1894 - 1966) also played an important role in modern Astronomy. A Belgian Cosmologist, as well as a Catholic priest, he was the first to propose the Big Bang as the origin of our universe. He called it the ‘hypothesis of the primeval atom’ and then later went on to name it ‘the beginning of the world’. The 20th Century blessed us with many brilliant, recognisable astrophysicists that popularised astronomy, propelling it into the mainstream.

The list is endless, from the likes of ALBERT EINSTEIN (1879 - 1955) EDWIN HUBBLE (1889 - 1953) SIR FRED HOYLE (1915 - 2001) STEPHEN HAWKING (1942 - 2018) JOCELYN BELL (1943) NEIL DEGRASSE TYSON (1958) to name merely few.

LOOKING FORWARD

The advances us as humans have made within the last two centuries alone are extraordinary. From stargazing and trying to map the stars with the naked eye, to large Telescopes with intricate features.

Currently we see about 1000 supernovae every year. At the Rubin Observatory in Chile, which will be fully operational in about 2023, we will be able to see 1000 supernovae per night. Astronomy is not only being used to decipher the wonders and origins of our universe, but is also being used for peace, as exhibited by the IAU Office of Astronomy for Development on their website. The example that is written about on the site is that of the island nation of Cyprus. The two communities, the GreekCypriots and the TurkishCypriots live separated from each other, in the South and in the North of the island. The Astronomy for Development organisation arranged several days of Astronomy activities, involving children from both sides. The activities took place at a community centre in the UN buffer zone between the North and the South of the island.The blog-post on the website explained, “this sense of goodwill extended to the adults involved. Teachers from both sides spoke about collaborating and are eager for future events”.

Bridging the gap between the divided nations was important, giving the children a safe space to interact, learn about Astronomy and build friendships. The next event is already being planned. Over the last Century alone, Astronomy has taken huge strides. If this trajectory is anything to go by, the world will see many great and pioneering moments in the 21st Century, as our knowledge of the Universe expands, leaving us with many new puzzle pieces to decipher and put together.