 IMPRINT EMAIL-KONTAKT © Eclipse-Journeys.com 2005 - 2007, all rights reserved |
|||
|
|||
|
RELATIVES OF AN ECLIPSE A solar eclipse never comes alone but will always be "accompanied" by a lunar eclipse, which is its (temporal) neighbour. And each solar eclipse is part of a series of about 75 geometric similar occurrences, which are known as Saros and so to speak represent its relatives. Due to the combination of 2 different series - saros and inex - there can be demonstrated numerous connections - which partly reach over thousands of years - between eclipse occurrences and also gain predictions for the distant future. If you want to know more about this theme we recommend the following sites: SAAO earthview.com Robert Harry van Gent Felix Verbelen. In the following we introduce to you the closest relatives and neighbours of the solar eclipse of 2008 August 01: To each solar eclipse belongs a lunar eclipse, which takes place around two weeks before or afterwards. In rare cases a solar eclipse is also flanked by two lunar eclipses, which then are both penumbral eclipses. Our solar eclipse in August 2008 is followed by a partial lunar eclipse on 2008 August 16, which can also be observed in Central Europe. A group of two or three solar and lunar eclipses is followed by the next “eclipse season” almost six months (about 173 days) later if the other node of the Moon’s orbit transits between Sun and Earth. After further 173 days, the eclipse year is then completed with the repeated transit of the first node of the Moon’s orbit between Earth and Sun. Since the eclipse year is about 20 days shorter than the calendar year the eclipses occur accordingly earlier each year. The situation gets complicated because the lunar year (time between the 1st and the 13th following new Moon) is with 355 days longer than the eclipse year. The total solar eclipse of 2008 August 01 is followed by the total solar eclipses of 2009 July 22 and 2010 July 11 as well as the partial solar eclipse of 2011 July 01. But then the series ends because of the different duration of lunar and eclipse year. Thus there will be no solar eclipse on the 20th or 21st June 2012. In return a new sequence, which reaches to 2014, has already started with the partial solar eclipse of 2011 June 01. After four (or sometimes five) years with solar eclipses which occur ten days earlier each, there is a leap of four or six weeks to the next series. The most famous sequence of eclipses that are not related to each other is probably characterised by the metonic cycle. After exactly 19 calendar years the same lunar phase falls (approximately) again on the same calendar day because 19 years are almost exactly 235 synodic months. Since there is a new Moon on August 1st 2008 this will be also the case on August 1st 2027. 19 calendar years equal also almost exactly 20 eclipse years. Because of this there will be another solar eclipse on 2027 August 02 (one day postponement is possible at times), also on 2046 August 02 and on 2065 August 02. Therefore the next eclipse could be expected on 2084 August 02. But this is not the case because 20 eclipse years are not exactly 235 synodic months, and because of this the series do not last long. Looking into the past there is no solar eclipse listed for the beginning of August 1989, too. The Saros is clearly more long-lasting (1200 to 1500 years). 19 eclipse years (= 18,03 calendar years or rather 18 years and 10 1/3, 11 1/3 or 12 1/3 days) are almost exactly 223 synodic and at the same time 239 anomalistic months (principle of the smallest common multiple). Because of this a very similar solar eclipse occurs after this time but 1/3 of the circumference of the Earth moved to the west. Therefore the solar eclipse of 2026 August 12 will to be observed over the Atlantic instead of in Asia. A saros period later, after 36,06 years, however, the solar eclipse is visible 120 degrees of longitude farther west. That is why on 2044 August 23 the black sun will appear in the west of Canada. The third following eclipse, after 54,09 years (this is called the exeligmos period), should then again visible at the same geographical latitude as the original one, however moved several latitudes to the north or south. Although the solar eclipse of 2062 September 03 is only partial you can easily see on the linked graphic that the highest degree of occultation will occur - as expected - over North Asia. The look back is so to speak mirror image but because of the eclipse’s paths which are close to the poles the postponement by 120° is not discernible straight away. On 1990 July 22 the eclipse’s path passed through North East Europe, on 1972 July 10 through North Canada and parts of the North Atlantic. On 1954 June 30 the central zone took its course much further south than in August 2008 so that the black sun was visible in Scandinavia (one of the most famous eclipses of the 20th century!). In 1900 a solar eclipse of this saros series was already the goal of a scientific expedition (report). You find an overview of all eclipses of the saros series 126, that the solar eclipse of 2008 August 01 is part of, on Fred Espenak's pages. All solar eclipses of the saros series 146 mentioned here are followed by lunar eclipses of the saros series 138 as “loyal companions” until the 25th century. Saros 138 produces partial eclipses at increasing magnitude until 2026, but total ones from 2044 onwards. |
|||
| JOURNEYS TO THE TOTAL SOLAR ECLIPSE 2008 |