Astronomy should be studied by mankind because our survival is directly linked to the cosmos. The Earth is heated by its nearest star, the Sun, and its ocean tides are directly connected to its only satellite, the Moon. Knowledge of how these celestial bodies function and relate to each other is crucial to understanding the history of the Earth and where it may be headed.
Astronomy has virtually always been studied by mankind because, thankfully, certain individuals throughout history looked at the night sky and wanted to understand it and to be able to draw predictions about it. Considered, as the attached eNotes document states, the oldest form of science, astronomy dates back thousands of years when ancient Chines, Arabs and Greeks took it upon themselves to map the sky and identify both the constants, in effect, the constellations, and the aberrations, for example, the identification of the planets and comets. It was the German astronomer, Nicolaus Copernicus (1473-1543,) who risked his life to demonstrate that the Earth, and other known planets, rotate around the Sun during a period when conventional wisdom – supported by the omniscient Church – believed the Earth to be the center of the universe with the Sun rotating around it. And, it was the Italian astronomer, Galileo Galilei (1564-1642), who also risked his well-being by advancing a scientifically-grounded heliocentric theory in defiance of Church doctrine, and who is credited with major improvements to the telescope and the discovery of Jupiter’s moons and of sunspots. Given the importance of sunspots to our ability to function as a society – 2013 is a period known as a Solar Maximum, whereby solar activity directly connected to sunspots is at a peak with potential ramifications for the protection of electrical grids around the world – it could be argued that Galileo’s decision to study astronomy has benefit every man, woman and child on the planet.
Astronomy should also be studied because the universe is not a static model; on the contrary, it is constantly changing, and it is through the study of astronomy that we know that the Andromeda and Milky Way galaxies are on a collision course, that the Sun is halfway through its lifecycle, and that the potential for a major asteroid strike on the Earth is very real and life threatening. While the first two developments are hardly of daily concern to even the most nervous astronomer, the issue of a catastrophic asteroid strike is a high priority for many governments around the world.
Astronomy was developed as a science because of the intellectual curiosity of its early practitioners. Its growth as a field, however, owes a great deal to the direct relationship of the Earth to many other objects in space.