THE START OF SOMETHING NEW...
The Beginning of a New Idea...
Early astronomers, in different civilizations, used the observed motion of the stars, the Sun, Moon and planets as the basis for clocks, calendars and a navigational compass. The Greeks developed models to account for these celestial motions.
Copernicus, in the 16th century, was the first to explain the observed looping (retrograde) motion of planets, by replacing a geocentric heliocentric model of the Universe with a heliocentric model. Modern planetary astronomy actually began in the 17th century with Kepler, who used Tycho Brahe’s very accurate measurements of the planetary positions to develop his three laws.
Galileo contributed to the development of astronomy by teaching the Copernican view, and by devising a telescope which he used to show Jupiter’s moons as a model for the solar system, among other things.
Newton built on earlier insights with his universal law of gravitation and its fruits: predictions or explanations of Kepler’s laws, the motion of comets, the shape of the Earth, tides, precession of the equinoxes and perturbations in the motion of planets which led to the discovery of Neptune. He also had to invent the mathematics to do this: calculus.
Naming Heavens...
The names given to stars and constellations were rationalized by the German astronomer, Johann Bayer. In 1603, in homage to earlier Greek astronomers, he assigned the brightest stars of a constellation Greek letters in his star atlas Uranometria. So, the first star (usually the brightest, but not always) in any constellation would be alpha, followed by the genitive (or Latin possessive, meaning "belonging to") form of the constellation name. Using Orion as an example, the main star has the Arabic name of Betelgeuse, while the new Bayer designation became Alpha Orionis, or a Orionis. The possessives, as is the case with many languages, need to be learned as they are not simply the constellation name with "is" on the end. For example, the Latin possessive for Gemini is Geminorum and for Pegasus is Pegasi. In addition, all the constellations have a three-letter abbreviation, which make names quicker and easier to write. Orion is simply Ori, so Betelgeuse, again, could also be written as alpha Ori.
People Who Contributed to the Field of Astronomy...
Copernicus
Polish astronomer Copernicus (1473-1543) is considered to be the founder of modern astronomy. His studies of the orbits of the planets revealed that the Sun is at the centre of the Solar System. At the time, the predominant view was that earth was the centre of the universe.
Galileo
Italian astronomer and mathematician, Galileo (1564-1642) was the first person to use a telescope for studying the sky. He discovered the four largest satellites of Jupiter, today known as the Galilean moons. In 1610, Galileo improved the newly invented telescope to observe Jupiter's moons, lo, Europa, and used it to discover Ganymede, and Callisto.
Isaac Newton
English physicist and mathematician Newton (1642-1727) proposed the laws of motion that explain how forces move objects, and went on to devise a theory of gravity. Newton also studied optics, the science of light, and explained how white light is made up of many colour
Albert einstein
Einstein (1879-1955) was born in Germany but after Hitler came to power, he fled to the United States. Einstein revolutionized physics with his studies of relativity, which show how matter, energy, space, and time are connected. Einstein was awarded the Nobel Prize for Physics in 1921.