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Posts Tagged ‘galaxy’

Astronomy - Important Pre-Christian Dates

April 22nd, 2010

There is no uncertainty that astronomy is the oldest science and there is also no hesitation that astronomy was being studied by everyone, not only the wise men, thousands and thousands of years ago.

We do not know precisely why they did it, but we can surmise that early man noticed a correlation between the weather and the stars, which were themselves not fully understood, of course.

Early man, probably even as far back as Neanderthal man, noticed the relationship between the weather and herd movements and crop growth, or at least fruit and nuts on local trees, if they did not have planted crops.

This means that people could see a connection between the stars and food availability. This relationship was probably ritualized into some sort of religion like early Wicca. Therefore, the stars became a very important part of the lives of every single person and it is likely that astrology and astronomy were widely intermixed by the average person.

However, there were also people who did not only use the stars as some vast celestial clock and who tried to make sense of the whole shebang. I am going to narrate below, eight of the most important dates or years in the history of astronomy before Christ walked on the Earth. In no way forget that they had nothing but an abacus to do there calculations and no telescopes, which came about two thousand years later.

585 BC: Thales of Miletus (c. 625- c. 547), a Greek, predicted a solar eclipse in Asia Minor purely on the basis of his observations and calculations. It was not a lucky guess!

c. 400 BC: the astronomer Oenopedes (5th. century). also a Greek, announces that the Earth is tilted on its axis with respect to the Sun.

352 BC: the Chinese report what they called a 'guest star', a supernova, which was the earliest reported sighting.

340 BC: The astronomer, Kidinnu (b. Babylon c. 379 BC) discovers the precession of the Equinoxes, ie the apparent change in the position of the stars caused by the Earth's wobbling on its axis.

c. 300 BC: a 'committee' of Chinese astronomers compile star maps of the visible universe.

c. 240 BC: Chinese astronomers observe and make notes about Halley's Comet. Also Eratosthenes of Cyrene (c. 276 - c.194 BC), a Greek, correctly calculate the Earth's dimensions.

165 BC: Chinese astronomers notice sunspots for the first time.

c. 130 BC: the astronomer Hipparchus of Nicea (b. 147 BC), a Greek, correctly calculates the distance to the Earth's Moon and also rediscovers the precession of the Equinoxes.

You will see from the dates above that clearly not everyone let nature and the stars govern their lives, as the common farmer or hunter did. Some men actually put pen to paper, but before pen and paper even existed, and tried to work out 'why these manifestations took place?'.

These people must have been remarkable men to have worked these measurements out by calculation, observation by the naked eye and rationalization alone.

If you are fascinated by astronomy, then please visit our website at: http://astronomy.the-real-way.com

The Chinese Lunar Calendar

March 11th, 2010

Previous to their implementation of the Western solar calendar scheme, the Chinese almost exclusively followed their own lunar calendar for determining the times of planting and harvesting and festival days. Although people in China today use the Western calendar for almost all business, governmental and practical matters of daily life, the old system still serves as the basis for working out numerous recurring holidays. This coexistence of two calendar schemes has long been acknowledged by the people of China.

However, this does not only apply to China, it also happens in most other Eastern countries, like Thailand, and most Arabic countries.

A lunar month is calculated by measuring the period of time required for the moon to finish its full cycle of 29 and a half days, a standard that makes the lunar year a full 11 days shorter than its solar counterpart. This disparity is made up every 19 years by the addition of seven lunar months.

The 12 lunar months are further divided into 24 solar divisions characterized by the four seasons and times of heat and cold, all of which bear a close relationship to the annual cycle of agricultural work.

The Chinese calendar - very much like the Hebrew calendar- is a combination of the solar and lunar calendars in that it strives to have its years coincide with the tropical year and its months coincide with the synodic months. It is not surprising that a few similarities exist between the Chinese and the Hebrew calendar.

For example, an average year has 12 months, a leap year has 13 months. An ordinary year has 353, 354, or 355 days, a leap year has 383, 384, or 385 days. When determining what a Chinese year will be like, one needs to make a number of astronomical calculations.

First of all, you have to determine the dates of the new moons. In these cases, a new Moon is the completely black Moon (that is to say, when the Moon is in conjunction with the Sun), not the first visible crescent, as is used by the Islamic and Hebrew calendars. The date of a new moon is then the first day of a new month.

The reason why the majority of countries which had their own calendars had to drop them in favour of the Western, Julian calendar that we use today, is business. First the British and then the Americans ran international business and they used the Julian calendar.Anyone who wanted to work with them had to follow suit. This is why national policy often differs from local custom in Third World countries.

The government desires to deal on the International markets, but the ordinary family in the country can not. So, the government adopted the Julian calendar but the people only pay lip service to it. I live in Thailand and people here do not even use the 24 hour day divided into two halves. Their day has four sections of six hours each and the first part starts at 6AM, not midnight. Therefore, they have four 4 o'clocks a day, for example but no 7 o'clocks. They are also 543 years ahead of us, although this is more common, for example in Muslim countries.

If you are fascinated by astronomy, then why not pop along to our website at: Astronomy Today

Astronomy - An Introduction

January 8th, 2010

Despite the fact that astronomy is the oldest science, it is still at the forefront of not only scientific thought, but also that of the public at large. Who hasn't looked up at the galaxy while walking home late at night and wondered about something larger? Having said that though, the ancient people of definitely the northern hemisphere, but probably both hemispheres, knew the movements of the stars and planets better than the majority of us do nowadays.

They knew even then, thousands of years ago, that most stars appear to appear in the Eastern skies at night and travel on circular paths. They also noticed that some 'stars' were 'wanderers' (we call them planets) and that sometimes they travelled 'against the flow'.

They also named groups of stars that we now call constellations or even galaxies and knew that those visible in the winter were different from those visible in the summer.and that others were visible all year round. The average common man of 5,000 - 10,000 years ago almost certainly knew more about the movement of the celestial bodies than the average common man of today does. (I mean men and women here, of course).

They discovered how to work out or at least find the extremities of the sunrise and went to extraordinary lengths to mark those points with huge stone structures, such as Stonehenge in the UK, probably to facilitate the location of certain positions of the sun or other planets or stars, which may have been important to their religious beliefs or crop cycles.

In 1609, Galileo invented the first artificial device for studying the stars and planets. It was the first astronomical telescope and through it he was able to observe things millions of miles away that no one had ever seen before. Because of the deductions he drew from his observations, he clashed with the Roman Catholic Church and was often in serious danger for his life, so radical were his discoveries.

But mankind was not intimidated, and since then we have gone on to build ever bigger and ever better telescopes with which we can even detect radio waves, microwaves, X-rays, infrared waves and gamma waves from outer space. Forty years ago, we even travelled to our Moon. and we have sent probes to eight of the nine planets in our Solar System, as well as to several comets and asteroids.

Where are we going next? That decision was always up to the government of the United States and the old Soviet Union, but now there are other players in the field. What will China or India want to explore with their possibly slightly different outlook on life? Or will it be just a question of financial benefit?

The world may be in a state of flux and power may be shifting from its traditional seats in the West, but it has not diminished interest in questions that scientists think can only be answered in space. These are exciting times for the science of astronomy, but then man has always found astronomy exciting.

Fascinated by astronomy? Then please pop along to our website at: http://astronomy.the-real-way.com

Astronomy For Kids.

July 26th, 2009

Astronomy is a very serious branch of science, although a lot of people get involved with it when they are quite young. Astronomy is a thought-provoking hobby that can show children about the other sciences in general. Certain astronomical subjects inspire kids and movies like Star Wars and they only increase this interest.

Our only natural satellite is called the moon. Its orbit around the Earth takes just over twenty seven days to complete. Man's knowledge being what it is and because the moon is so near, it is the only space object that mankind has ever set foot on, except for the Earth of course. The effects of gravity between the moon and Earth causes the seas' tides. The moon is one of the first objects that sparks a child's interest in astronomy because it can be clearly seen with the human eye.

Let's consider the sun. Earth is quite far from the sun, although the distance actually fluctuates between about 91 million miles and about 94 million miles. The reason for this variance is because of Earth's elliptical orbit. Life on Earth is only possible because of the sun, which is our source of important elements such as light and heat. A little-known fact is that the sun contains about 98% of the mass of the whole solar system! Just think about how small a person is compared to that.

We live in the galaxy called the Milky Way. Like all other galaxies it's a collection of gas, dust, stars and planets. Most of the area in a galaxy is filled with nothing, just empty space. That means that most of its volume, 3,000 light years high by 100,000 light years diameter, the volume of our galaxy, is empty.

Our Earth is situated somewhere in the vicinity of 30,000 light years from the central core of our galaxy. The emptiness is broken up by over 100 billion stars. In fact, the galaxy was named after the thick group of stars in the main portion of it.

It looks just like a pool of liquid, which is why it was given the name Milky Way. There are four sorts of galaxies: elliptical, lenticular, irregular and, like the Milky Way, spiral.

There is a great deal of information about astronomy that is fit for children on the Internet: from dictionaries and encyclopaedic references to programs that show different planets, solar systems and objects right on the computer's monitor! In fact, there's more information than a child could ever read.

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Fun Facts about Astronomy

June 7th, 2009

Astronomy is an interesting science to many people because it is stuffed with loads of fun astronomy facts. Everything from the size and temperature of our own star, the Sun, to the make-up of distant planets has been recorded. All of this information can be retold to entertain and enlighten your friends.

The Sun is a great source of astronomy fun facts. Our own star that supplies us with all our heat and light is between 91 and 94.5 million miles from Earth. It's not that nobody knows the distance for certain. It's that the Earth revolves around the Sun in an elliptical, uneven, orbit, so the distance varies depending on where the Earth is situated in that orbit.

The Sun is only of average size for a star, yet it's size is another terrific source of astronomy fun facts. As average as it is, it accounts for about 98% of all the matter in our solar system. Even with the huge planet of Jupiter on our side, we're still a tiny 2% of non Sun stuff.

It would take the diameter of about 100 Earths to measure across this average Sun. The solar winds produced by the Sun extends to about 50 times the distance from the Earth to the Sun. In other words, those solar winds go out about 50 AU's, with an AU being the distance from the Earth to the sun. That's quite amazing, isn't it?.

How about astronomy fun facts that don't have anything to do with the Sun then? How about the Moon? It's the only non-Earth object that man has walked upon so far. And one man actually travelled to the Moon but never left it. Dr. Eugene Shoemaker loved the Moon but was rejected as an astronaut. After his death, he was cremated and his ashes were scattered over the Moon by the Lunar Prospector spacecraft in 1999.

There are many more astronomical fun facts about the Moon. It's where what might become the oldest footprint known to man. Neil Armstrong's giant leap for mankind left a footprint or shoe print in the Moon's dust that will probably still be there in 15 million years time.

Many people, in fact about 13% of those asked in 1988, still believed the Moon is made of cheese. And finally the suits worn by the Moon-walking astronauts weighed 180 pounds on Earth but only 30 pounds on the Moon, because of the reduced gravity on the Moon. Talk about an instant diet, eh?

Astronomy fun facts aren't limited to our close astronomical neighbours. Looking at stars is like looking into the past. Some of the stars we see today in the night sky are so far away that their light takes a million years to reach Earth. Some of the stars you see may really be images of stars a million years old that aren't even there in the present. There are over 1 x 10 ^22 stars in the universe. That's a 1 followed by 22 zeros. The number is really quite staggering.

There are thousands of astronomy fun facts that we could go on about. But, unfortunately, this article can not be that long. So, please, just get out there at night, look upwards and learn more about astronomy for yourself.

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