Young Edmund was tutored privately in his home for many years until he entered Saint Pauls School. There, he excelled in all he did, becoming the captain of the school at the age of 15. At the age of 17, he entered Queen's College Oxford, already an expert astronomer. He carried with him the wonderful collection of astronomical instruments purchased for him by his father.
During college, Edmund worked with the Astronomer Royal, John Flamsteed, and the Royal Observatory in Greenwich. He was also making some of his own observations. On August 21, 1676 he observed an occultation of Mars by the Moon, which he published in Philosophical Transactions of the Royal Society.
While his mentor John Flamsteed began mapping the northern sky, Halley decided to map the southern sky. He traveled to St Helena Island, the southernmost point of the British empire. There, he catalogued many of the stars which can be seen from the southern hemisphere (the southern half of the Earth), while Flamsteed worked on the northern stars.
He did a lot of other great things in his life, including taking over as Astronomer Royal when John Flamsteed died, but he is best known for figuring something out about some comets.
People had seen comets in the years 1456, 1531, 1607, and 1682. After studying records about these comets, Edmund Halley used Newtons theories on elliptical orbits to figure out that they were all the same comet, whose orbit carried it back again every 75 or 76 years. Some people did not believe him when he said that this comet would come back in 1758.
Edmund died on January 14, 1742 in Greenwich, England, which is also near London. He did not get to see the comet come back in 1758, like he said it would. He also did not know that people named the comet after him.