Without him, Newton would have taken all his ideas to his grave: Who is Edmond Halley?

Edmond Halley was born on 8 November 1656 in Haggerston, London. His father was a wealthy soap maker with the same name. When Halley was only ten years old, his father suffered great losses in the great fire in London. However, despite this, he made an effort to ensure that his son received a good education. He first received private education at home and then started his education at St Paul's School.

Even in his childhood, mathematics had a special place for him. After graduating, he went to Queen's College, Oxford, for his undergraduate studies. Here he continued his studies in mathematics and astronomy. However, he felt his education was not progressing fast enough. He left his university education in 1676.

Edmond Halley (8 November 1656 – 25 January 1742) was an English astronomer, mathematician and physicist. He was the second Astronomer Royal in Britain, succeeding John Flamsteed in 1720.

Young Edmond was a genius. Before leaving Oxford, he had corrected established star charts and published a paper detailing methods for calculating eccentric planetary directions. The fame he gained at an early age through these works gave rise to a deep-rooted desire to continue his own research.

He wanted to help map the positions of the stars, but realizing that England's royal astronomer John Flamsteed had already made a start, he came up with the idea of mapping the stars of the southern hemisphere. For him, this was more important than finishing his degree at Oxford. Using his father's connections, he managed to persuade King Charles the Second, a ruler respectful and supportive of scientific ideas, to allow him to travel to the British island of Saint Helena, where he set up his instruments and mapped the stars of the southern hemisphere. Thus, Halley's scientific journey officially began.

Halley spent a year on Saint Helena, a small Atlantic island halfway between Brazil and Angola. Here, as long as weather conditions allowed, he mapped the stars of the southern hemisphere. These stars were almost unknown to Europeans until then. Sailors saw them crossing the southern oceans, but European astronomers had no knowledge of what lay below the horizon.

Halley prepared the first map of the southern sky. He recorded the positions of more than 300 stars and discovered several constellations. Additionally, Halley noted the relationship of the southern stars to the northern stars that he could see from Saint Helena. This would later enable astronomers to combine the two hemispheres into a single map.

Halley returned to England and presented his work to the Royal Society of London for Improving Natural Knowledge, England's leading scientific organization. Their maps were successful. Shortly afterwards he was elected a fellow of the Royal Society. King Charles was pleased with the results of Halley's work. When Oxford University refused to award Halley his degree, stating that he had violated the residence requirement, King Charles intervened and ordered the university chancellor to award the diploma. Thus, Edmond Halley received his diploma without completing the course.

Halley and Newton

A few years later, Halley became interested in orbital mechanics and the path of comets moving through space. During this time, he met Isaac Newton, a reclusive mathematics teacher at Cambridge University who could not make progress on his own.

Newton had begun to formulate mathematical equations that described a force he called "gravity" and how this force governed the motion of objects. Although Newton was extremely promising, he sank into darkness after Hooke, one of the great physicists of his age, harshly criticized Newton's studies on optics, and devoted himself to unraveling the occult teachings and the numerological secrets of the Bible. He needed a driving force to get rid of these obsessive ideas and return to science.

Halley served as a catalyst for Newton's return to science. He encouraged him to write down his thoughts and promised to arrange for the Royal Society to publish a book.

Newton eventually responded to Halley's efforts and wrote Philosophiae Naturalis Principia Mathematica, one of the most important works of the scientific revolution. This investigation established a theoretical basis for understanding orbital mechanics. Meanwhile, Newton created calculus, one of the new and most fundamental branches of mathematics.

But there was a small problem: When Halley took Newton's book to the Royal Society for publication, he learned that the society had spent its entire publishing budget on a treatise called The History of the Fish, which was deemed to be of zoological importance. The Society had no budget to publish Newton's groundbreaking work.

Halley was ready to take full responsibility for the broadcast. He covered the printing and distribution costs from his own pocket. Newton may have written the book, but if Halley had not put so much pressure on him to do so and assumed all the expenses involved in the publishing process, Newton, the taciturn man, might have taken all his ideas to his grave.

In other words, Halley was the major stakeholder in Newton's great work—and the biggest return on Halley's investment in Newton's science would be one of Halley's greatest discoveries.

In 1681, Giovanni Domenico Cassini told Halley about his theory that comets were orbiting objects. In September 1682, Halley made a series of observations of the celestial object that became known as Halley's Comet (you can read more about this comet here). Because of his work on the orbit of this object and his prediction of the object's return in 1758, the name of the comet became associated with it (unfortunately, Halley never got to see this return).

In early 1686, Halley was elected to the new position of secretary of the Royal Society. Due to his duties within the position, he had to do a lot of correspondence and manage meetings; he also took over as editor of the journal Philosophical Transactions and was therefore forced to abandon his scholarship.

The celestial realm was not the only sphere that occupied Halley's thoughts. Halley became interested in the movement of wind, especially the trade winds. The first scientist to map the movement of dominant currents was Halley. He designed a weather chart with wind direction indicators that are still used today. Halley also developed the proposition that air moves from areas of high pressure to low pressure and is responsible for the flow of wind.

Halley became interested in scientific studies of measuring the age of the earth. Starting from the premise that the seas must have contained fresh water when the world was created, he developed ideas about whether it would be possible to use the current salt content to determine the length of time the seas existed. For centuries, it was believed that rivers flowed downstream to where salt collected in the oceans. By measuring the increasing salinization rate over time, it would be possible to calculate towards a time when the sea was salt-free, possibly to the date of creation.

Halley tracked the salt content of the sea over a period of time. In light of this pursuit, he conducted experiments and created the mathematics of the results. These studies showed that the earth was at least 100 million years old. While this was much shorter than the 4.5 billion years accepted today, it was significantly longer than the period accepted by the church. The church did not like this situation at all.

Although Halley was an excellent mathematician, he is not known for his contributions to the discipline, with one exception.

Edmond Halley, who died on January 25, 1742, had a long and productive scientific career. Although it is written in many texts that he received the title "Sir", this is not true; Erroneous information on this subject has probably arisen due to its closeness to Sir Isaac Newton.

Halley, who is interested in almost every field of science, made important contributions to many fields. Although he is remembered today only for predicting the path of a comet across the sky, he was actually one of the greatest minds of the scientific revolution.