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Total solar eclipse of July 22nd 2009
On 22nd July 2009 the longest total eclipse of the 21st century will track across the globe from the west coast of India, across the Himalayan mountains, through central China and on over the Pacific Ocean. The map below shows the path the eclipse will take. Naturally the climax of this eclipse tour is the day of the total eclipse itself, a day exclusively reserved for observing, experiencing and reliving the experience. The other days are a combination of not only a number of famous highlights but everyday China as the itinerary has been made to give as wide an impression as possible of this fascinating country. We will be observing the eclipse in the countryside north of Leshan. This affords better visibility than viewing close to the larger cities where there is significantly more air pollution.
China and eclipses
The ancient Chinese invented the first planetarium which was actually made by an emperor. The planetarium was a large enclosed place with stars and constellations on the inside. The person using the planetarium would sit in a chair that was hanging from the top of the enclosed dome. Ancient Chinese astronomers already had sophisticated observatory buildings by 2300BC. Because observing total solar eclipses was a major element of forecasting the future health and successes of the emperor, astrologers were left with the onerous task of trying to anticipate when these events might occur. By about 20BC, surviving documents show that Chinese astrologers understood what caused eclipses, and by 8BC some predictions of total solar eclipses were made using the 135-month recurrence period and, by 206AD, Chinese astrologers could predict solar eclipses by analysing the Moon's motion.
Ancient Chinese astronomy was primarily a government activity. It was the astronomer's role to keep track of the solar, lunar and planetary motions as well as divine what astronomical phenomena may mean for the ruling emperor. Solar eclipses, infrequent and dramatic, were important enough to be recorded in chronicles and on "oracle" bones in the Shang dynasty (c. 1600-1050BC). Oracle bones are pieces of animal bones and tortoise shells inscribed with astronomical observations that were probably used for divinations.
Chinese and European astronomy
In 1669, the emperor Kangxi was informed that serious errors had been found in the calendar for 1670, which had been drawn up by Yang Guangxian. Kangxi commanded a public test to compare the merits of European and Chinese astronomy. The test was to predict three things: the length of the shadow thrown by a gnomon of a given height at noon of a certain day; the absolute and relative positions of the sun and the planets on a given date; and the exact time of an anticipated lunar eclipse. It was decided that Yang and the Belgian Jesuit, Ferdinand Verbiest, should each use their mathematical skills to determine the answers and that "The Heavens would be the judge". The contest was held at the Bureau of Astronomy in the presence of senior-ranking government ministers and officials from the observatory. Unlike Yang, Verbiest had access to the latest updates on the Rudolphine Tables, and was assisted by telescopes for observation. He succeeded in all three tests, and was immediately installed as Head of the Mathematical Board and Director of the Observatory. Yang lost the contest and his life. After this, Verbiest and the emperor formed a real friendship, with the Jesuit teaching him geometry, philosophy and music. Having resolved the issues surrounding the calendar, Verbiest went on to compose a table of all solar and lunar eclipses for the next 2000 years. Delighted with this, the emperor awarded him complete charge of the imperial astronomy observatory, which he rebuilt in 1673. The existing equipment was obsolete, so Verbiest consigned it to a museum and set about designing six new instruments: the altazimuth, celestial globe, ecliptic armilla, (this was the traditional European device while the Chinese developed the equatorial armilla), equatorial armilla, quadrant altazimuth and a sextant. These were all very large, made of brass and highly decorated, with bronze dragons forming the supports. Despite their weight, they were very easy to manipulate, demonstrating Verbiest's aptitude for mechanical design. These instruments we will see when we visit the Beijing Observatory.
Travelinck and Leiden Observatory
Founded in 1575, Leiden University is the oldest university in the Netherlands and here astronomy has a long tradition. In 1633 an observatory was established which means Leiden Observatory is the oldest university observatory in the world still in operation.
In the first two centuries of its existence its purpose was mainly educational. The construction of a spacious new observatory building in 1861 under the supervision of F. Kaiser was the beginning of the modern era of astronomical research in Leiden. This building on the Witte Singel was the home of Leiden astronomy for over a century, and continues to be a powerful symbol for anyone, child or adult, who has gazed at the stars and wondered.
Since 1974, Leiden Observatory has been housed in a new complex. Now astronomy is done by modern means, the institute has grown in size and scope and it still stands at the forefront of astronomical research. The old observatory, however, is still in use for outreach activities such as tours and popular lectures. Furthermore, amateur astronomers continue to use the telescopes on site for their observations. In 2009 the Observatory started extended refurbishments after receiving 2.8 million euros from the Ministery of Education, Culture and Science.
Dr. Dave Lommen, an astronomer working at the Observatory in Leiden, will be the eclipse expert travelling with the group. Dave is passionate about explaining the wonders of the skies to a general audience. Besides his Ph.D. thesis work over the past four years, he has participated in a large number of outreach activities, which included several popular talks at the Old Observatory.
The year 2009 is the International Year of Astronomy and with the eclipse in Asia being one of the longest in our lifetime, it is to be celebrated. This tour of China and the eclipse experience is expected to lead to the publication of a book on the subject. With the combined expertise of Travelinck and the contributions from the Observatory, an ideal and well-planned itinerary has been created to give an unforgetable eclipse experience and a memorable impression of China and her people.
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