The History of Astronomy

By Arpit and Hamzah Ismail

Since the beginning of the universe, people have looked up at the stars, the sky and always wondered what’s out there. The twinkling stars, the shifting constellations and occasional celestial events like eclipses and comets have sparked curiosity and led to the development of astronomy. As we delve deeper into this topic we journey through the ancient myths, early observations and groundbreaking industries that have shaped our understanding of the cosmos.

Ancient Astronomy

A new study says that some of the world’s oldest cave paintings reveal that ancient people had relatively advanced knowledge of astronomy. According to the new analysis, some of the paintings are not simply depictions of wild animals, as was previously thought. Instead, the animal symbols represent star constellations in the night sky, and are used to represent dates and mark events such as comet strikes.

Researchers from the Universities of Edinburgh and Kent studied details of Paleolithic and Neolithic art featuring animal symbols at sites in Turkey, Spain, France and Germany. They found all the sites used the same method of date-keeping based on sophisticated astronomy, even though the art was separated in time by tens of thousands of years.

According to the study, published November 2, 2018, in the Athens Journal of History, the cave paintings suggest that, perhaps as far back as 40,000 years ago, humans kept track of time using knowledge of how the position of the stars slowly changes over thousands of years.

For example, the findings suggest that ancient people understood an effect caused by the gradual shift of Earth’s rotational axis. Discovery of this phenomenon, called precession of the equinoxes – motion of the equinoxes along the ecliptic (the plane of Earth’s orbit) – was previously credited to the ancient Greeks.

In ancient Egypt, stars held deep religious and spiritual symbolism. Egyptians associated stars with their belief in an afterlife, considering them as the eternal souls of the deceased. They believed that the stars' mesmerizing glow represented the immortality of the human soul and its journey through the celestial realm.

Ancient Egyptian texts also suggest that stars served as guides for the souls of the deceased during their journey to the afterlife. The alignment of stars, particularly the constellation of Orion, played a crucial role in determining the path of the soul through the Duat, the underworld in Egyptian mythology.

Greek astronomy had its roots in the much older work done in the Babylonian and Egyptian civilisations. Over a thousand years before Greek astronomy began, the Babylonians already had extensive astronomical records, with good measurements of time, and of the positions of the moon, stars and planets in the sky.

Geocentrism, the idea that the Earth was at the center of the solar system (or even cosmos) and that the other heavenly bodies, including the sun, moon, and the planets revolved around it, was dominant in ancient Greece and ancient cosmographical systems more generally. However, various alternatives appeared at one time or another. For example, the Pythagorean astronomical system, as proposed by Philolaus in the 5th century BC, proposed that there was an unseen "Central Fire" (not to be confused with the sun) around which all other bodies of the cosmos revolved. In the 3rd century BCE, Aristarchus of Samos was the first and only premodern figure to propose a truly heliocentric model of the Solar System, placing the sun, not the earth, at the center.

Hindu contributions to ancient astronomy are profound, with early scholars like Aryabhata laying the foundations for many modern astronomical principles. In the 5th century CE, Aryabhata proposed a heliocentric model and made remarkably accurate calculations of the solar year, eclipses, and planetary motions. The Surya Siddhanta, an influential astronomical text, introduced advanced trigonometric methods and described celestial phenomena in detail, influencing both Hindu rituals and global scientific thought. These innovations, coupled with the integration of mathematics and astronomy, significantly shaped the development of astronomy in the Islamic world and later in Europe, illustrating the lasting impact of Hindu intellectual traditions on the global understanding of the cosmos.

Medieval and Islamic Era

During Europe's Dark Ages (5th to 10th century), much of the astronomical knowledge from ancient Greece and Rome was lost, leading to a significant decline in scientific progress. However, during this same period, the Islamic world was experiencing its Golden Age (8th to 14th century), where scholars preserved and expanded upon the knowledge of earlier civilizations.

Islamic astronomers refined tools like the astrolabe and made significant contributions through detailed observations and calculations, which corrected and improved upon earlier Greek models. These advancements played a crucial role in preserving knowledge and ultimately influenced the later European Renaissance.

The Renaissance and the Birth of Modern Astronomy

During the Renaissance, Christian scholars played a crucial role in the birth of modern astronomy. Figures like Nicolaus Copernicus, a devout Catholic, revolutionized the field with his heliocentric theory, challenging the Earth-centered model. Johannes Kepler, a Lutheran, further advanced astronomy by formulating the laws of planetary motion. Their work, deeply intertwined with their Christian faith, laid the foundation for the Scientific Revolution, merging ancient knowledge with new discoveries to transform our understanding of the cosmos. This era marked a shift from old beliefs to a more scientific approach, setting the stage for modern astronomy. This period also saw the rise of the scientific method, which emphasized observation and experimentation. These advances set the foundation for modern astronomy and changed how we view our place in the cosmos.

19th Century Advances

Astronomy underwent significant transformation in the 19th century. The field grew beyond the cataloguing of celestial objects to include the knowledge of their origins and makeup. Finding asteroids like as Vesta and Ceres between Mars and Jupiter has led to new discoveries about our solar system. During this time, the planet Neptune was also found thanks to Adams and Leverrier's mathematical predictions. This demonstrated the amazing ability of mathematics in astronomy. Astrophysics emerged as a result of spectroscopy, which was developed by Bunsen and Kirchhoff and enabled scientists to examine the chemical makeup of stars and the Sun. Techniques like spectral analysis and photography were developed during this time, revolutionising our view of the universe and laying the foundation for contemporary astronomy.

20th Century

The twentieth century was a watershed moment in astronomy, highlighted by significant discoveries and improvements that altered our knowledge of the universe. Our understanding of the universe was changed in 1915 when Albert Einstein's theory of relativity redefined gravity as the curvature of space-time. The Big Bang theory, which explains the creation of the universe, was supported by Edwin Hubble's discovery in the 1920s that the cosmos is expanding. This notion was reinforced when cosmic microwave background radiation was discovered in the 1960s. The Apollo moon landing in 1969 and the advancement of robotic space exploration—such as NASA's Mars rovers, which completely changed our understanding of the solar system—also occurred this century. Together, these accomplishments broadened humanity's perspective of the universe.

Recent Accomplishments

In this century, astronomy and space exploration has made huge leaps thanks to modern technology. The James Webb Space Telescope, which launched in 2021, is helping us see farther into space than ever before, revealing new details about stars and galaxies. There’s also a lot of excitement around the idea of colonizing Mars, with NASA and private companies like SpaceX led by Elon Musk, pushing forward ambitious plans to make it turn into a reality from our imagination. These advancements are opening up new possibilities for exploring and understanding the universe like never before.