A partial solar eclipse was visible over parts of the southern hemisphere today (Nov. 25), as the moon passed between Earth and the sun for the fourth and final time this year.
The moon's penumbral, or outer, shadow will brush the southern belly of the Earth, according to Space.com.
Initially it will be visible touching down in the South Atlantic Ocean, about 600 miles (1,000 kilometers) a southwest of Cape Town, but only managing to encompass the southern and western portion of South Africa, completely missing Lesotho and barely grazing the border of Namibia. The sun will be seen rising with a dent in its upper right rim.
The eclipse was also visible in Tasmania, and most of New Zealand, according to NASA scientists...
The first eclipse on Jan. 4 coincided with sunrise across Europe.
Some Alaskans and Canadians shared a view of a partially obscured sun on the afternoon of June 1.
Solar eclipses are some of nature's most dramatic celestial events, and occur when the Earth, moon and sun are aligned on the same plane.
Partial solar eclipses happen when the moon partly covers the sun as it travels between our planet and its closest star...
"These are truly remarkable events", says Mark Trumball of Charlotte, N.C. "People, sometimes referred to as "eclipse chasers" or "umbraphiles", will travel to remote locations to observe or witness a predicted solar eclipse" he said.
NEXT ONE ON MAY 20, 2012
The next solar eclipse, on May 20, 2012, is expected to be a stunning event, and will be visible from China, Japan and parts of the United States. During this so-called annular solar eclipse, the moon will cover a large portion (but not all) of the sun.
BE CAREFUL
For those watching this, make sure to wear eye protection. By that I mean something more than just a pair of dark sun glasses.
Regular sunglasses do not adequately block enough of the infrared and ultraviolet radiation coming from the sun during the event, so specially designed "eclipse glasses" are needed, NASA scientists have said. These protective eyepieces use appropriate filtration for solar observation...
INFORMATION ABOUT SOLAR ECLIPSES
Total solar eclipses are rare events.
Although they occur somewhere on Earth every 18 months on average, it has been estimated that they recur at any given place only once every 370 years, on average.
The total eclipse only lasts for a few minutes at that location, as the Moon's umbra moves eastward at over 1700 km/h. Totality can never last more than 7 min 31 s, and is usually much shorter: during each millennium there are typically fewer than 10 total solar eclipses exceeding 7 minutes. The last time this happened was June 30, 1973 (7 min 3 sec).
Observers aboard a Concorde aircraft were able to stretch totality to about 74 minutes by flying along the path of the Moon's umbra. The next eclipse exceeding seven minutes in duration will not occur until June 25, 2150. The longest total solar eclipse during the 8,000 year period from 3000 BC to 5000 AD will occur on July 16, 2186, when totality will last 7 min 29 s. For comparison, the longest eclipse of the 20th century occurred on June 20, 1955 and lasted 7 min 8 sec.
If the date and time of any solar eclipse are known, it is possible to predict other eclipses using eclipse cycles. Two such cycles are the saros and the inex. The saros is probably the best known and one of the most accurate eclipse cycles. The inex cycle is itself a poor cycle, but it is very convenient in the classification of eclipse cycles. After a saros finishes, a new saros series begins one inex later, hence its name: in-ex. A saros lasts 6,585.3 days (a little over 18 years), which means that after this period a practically identical eclipse will occur.
The most notable difference will be a shift of 120° in longitude (due to the 0.3 days) and a little in latitude. A saros series always starts with a partial eclipse near one of Earth's polar regions, then shifts over the globe through a series of annular or total eclipses, and ends at the opposite polar region.
A saros series lasts 1226 to 1550 years and 69 to 87 eclipses, with about 40 to 60 central.
Frequency per year
Solar eclipses can occur 2 to 5 times per year, at least once per eclipse season. for more information see nasa.com for details.
Robert Tilford
Charlotte, N.C.
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