Astronomy
From the Simple English Wikipedia, the free encyclopedia that anyone can change
Astronomy is looking at and the study of planets, stars, galaxies, and other objects found in outer space. Astronomy is one of the oldest sciences. It has been done since long before written history began.
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[change] Early astronomy
The early astronomers were traders and sailors who needed the stars to guide them at night. Farmers, who needed to find out when planting, flooding, or harvesting times were coming, looked at the rising and setting of certain constellations in the sky. Ancient people who built things like Stonehenge, and the native North American medicine wheels, probably studied the sky for religious or sacred reasons. All these people needed accurate knowledge of the phases of the Moon, the most north and most south seasonal points of the sun, and other information for their purposes.
Some folks called astrologers believe they can predict the future by studying where the planets are in the sky when a person is born. Astrology is not regarded as a science these days. In the past, Astrology and Astronomy were closely linked, and people kept careful records of what they saw. These records have been very important to astronomers during the past two centuries, as they were trying to understand the Universe.
[change] History of Astronomy
Early people studied the stars using only their eyes as telescopes and binoculuars had not yet been invented. People saw some of the planets such as Mars and Venus, and studied Earth's Moon. People made maps of the stars positions and movements and used these for navigation. Early astronemers thought that the Sun and the stars went around or orbited the Earth when in fact it is the other way round. This was what everyone believed for hundreds of years. But later, during a time called the Renaissance, a man called Nicolaus Copernicus proved the right idea, that the Earth moves around the sun. He came up with the idea of a Solar System where the Earth and planets move around the Sun.
His idea was improved on by an important man called Galileo Galilei. Galileo helped to create the telescope which made it possible for people to see things much farther away. Galileo got into trouble with the church though becuase he argued against the idea that Earth was the center of everything. The Pope passed an order that made Galileo stay in his house and publish no books for most of his life.
After Galileo people used telescopes more often and began to see futher away objects such as the planets Uranus and Neptune. They also saw how stars were simlar to our Sun, but in a range of colours and sizes and other far away objects such as nebula.
Since the 20th century Astronomy has progressed a lot. It is now possible to use very big telescopes like the Hubble Space Telescope to look at stars and galaxies billions of miles away. Astronomers now use giant transmitters to look at things using x rays and radio waves.
[change] Being an astronomer
Not only is astronomy a very old pastime; it is also one that ordinary people can do with very cheap equipment. There are two types of astronomers: professional and amateur. Often the only difference between them is that amateurs don't get paid for their work. Amateur astronomers have discovered a lot of new and useful things, usually about new asteroids or comets, but sometimes about events such as the birth or death of stars. People often think they need an expensive telescope to look at the stars, but in fact all that is needed to get started is a pair of binoculars. However, if one is planning a more difficult project, such as the Hubble Space Telescope, much more expensive equipment will be needed. One famous amateur astronomer is Sir Patrick Moore, who presents "The sky at night" (BBC TV, UK).
Binoculars are the best tool for a new astronomer. Many new astronomers start off by buying expensive or poorly-made telescopes, but do not know how to use them. Then they find that they do not know what they are looking at, and soon become frustrated and go on to another hobby. A person starting out should first buy a book or a chart showing the constellations and most important stars, then take some time to learn and understand the movements of the Earth, the moon, and the planets. Then one can begin to learn about the sky with only eyes, binoculars, and a simple journal like a notebook, taking notes about what is seen.
Other reasons binoculars are so good for beginners are that they don't cost much, and they can be easily and quickly taken out of their case without lots of setting up and taking down again, as is done with a telescope. With binoculars interesting things can be seen, such as the moon's craters, double stars, many star clusters such as the Pleiades, and the moons of other planets. Binoculars are even better than telescopes for looking at things like the closer galaxies or very bright comets. Once one is familiar with the main star constellations and other main features of the night sky, then it may be time to buy a telescope.
[change] Kinds of astronomy
Astronomy has become a very large science in the past few hundred years, and there are many different types of astronomy.
Lunar astronomers study the moon, while planetary astronomers study the planets near our sun, and the planets near other stars. Some astronomers study special types of stars, like when two stars are next to each other. Other astronomers study distant galaxies, which are very large groups of many stars.
There are also astronomers who never look at the sky at all. These theoretical astronomers use physics and mathematics in combination with computers to create models of how the universe behaves, then they compare their models to what is observed. They want to understand and predict the events which happen in the universe, and understand how the universe was formed.
[change] Related topics
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