Astronomy is a natural science that studies celestial objects and phenomena. It applies mathematics, physics, and chemistry in an effort to explain the origin and evolution of those objects and phenomena and has been instrumental in developing our understanding of the Universe.
The word astronomy comes from the Greek words ἀστρον (astron), meaning “star”, and νόμος (nomos), meaning “law” or “order”. Astronomy should not be confused with astrology, the belief system which claims that human affairs are correlated with the positions of celestial objects. Although the two fields share a common origin, they have distinct purposes: astronomy seeks to understand the Universe as a physical entity, while astrology attempts to forecast human events through interpretation of astronomical data.
Early astronomers were able to make relatively accurate observations with little more than their eyesight and simple tools like quadrants. But as telescopes improved over time, so too did our ability to study distant objects in greater detail. Today we use some of the largest telescopes in the world to observe everything from nearby planets to galaxies billions of light years away. We also use spacecraft like NASA’s Hubble Space Telescope to take images and gather data that would be otherwise unattainable.
Through centuries worth of observations, scientists have pieced together a fairly comprehensive picture of how our Universe works. We now know that it is around 14 billion years old and consists of hundreds of billions of stars held together by invisible dark matter and dark energy. Our own Solar System resides on the edge of one spiral arm of our home galaxy – The Milky Way – which itself contains over 200 billion stars!
There is still much mystery surrounding our Universe though, particularly when it comes to dark matter and dark energy – what they are exactly remains largely unknown despite intense research efforts. Additionally, there are many questions about the formation and evolution galaxies, star formation within galaxies, as well as planetary formation around stars. With continued advances in technology coupled with an insatiable thirst for knowledge amongst astronomers worldwide; it’s safe to say that many more exciting discoveries await us in this most fascinating field of study!