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Old 2009-07-21, 19:28   #1
Raman's Avatar
"Mr. Tuch"
Dec 2007
Chennai, India

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Default Total solar eclipse tomorrow

There is a total solar eclipse visible tomorrow from India, China and the Pacific. This eclipse belongs to Saros 136, and lasts for 6 minutes 39 seconds at the central location which lies about 1000 kilometers south of Tokyo, Japan. This is the longest total solar eclipse of the century. The following animation shows the path of moon's umbra and penumbra during the tomorrow's solar eclipse.

Saros is a period of 6585.3 days (18 years 11 days) after which similar eclipses will occur. It is the period after which 223 New Moons and 242 transits of the moon across the plane of Earth's orbit coincide. I mean 242 times for the moon to travel from the ascending node to the descending node and back to the ascending node. These two nodes are points at which the moon's orbit crosses the plane of the Earth's orbit.

Since it is 1/3 days extra than a whole number, the Earth would have rotated 120 degrees west, so that we can view the eclipses at the different parts of the world. Such similar eclipses are named with the same Saros series number. After 3 such Saros series, (54 years 1 month 1 day) we can view a similar eclipse across the same part of the globe, but shifted either North or South.

For any total solar eclipse, the width of the moon's umbral shadow is not more than 300 kilometres of the Earth's surface. Not all solar eclipses are total, some are annular because the moon is at apogee to cover the Sun completely, so it leaves a ring of Sun around visible. Hybrid solar eclipses occurs when the moon's umbral shadow is just long enough to reach the Earth. The central location, very small place, will view a total solar eclipse, while the places at sunrise and sunset will view an annular solar eclipse. Places at the moon's penumbra will view a partial solar eclipse.

An annular solar eclipse occurs on 15 January 2010, whose central duration is 11 minutes 7 seconds and occurs near Maldives. It is the longest annular solar eclipse of the century. Lunar eclipses are of three types: penumbral, partial, total. During the penumbral lunar eclipse, the moon passes through the Earth's penumbra, though the moon is not completely eclipsed, the moon becomes dimmer. Since the Earth's umbral shadow is bigger than the moon's umbral shadow, a total lunar eclipse can last upto an hour and half, and can be viewed with the naked eye directly, and also that half of the globe that is facing the moon can see it up too.

Here are a list of upcoming solar and lunar eclipses.
Solar Eclipses:
2009 July 22 - Total, visible from east Asia and the Pacific
2010 January 15 - Annular, visible from east Africa, south Asia and south east Asia
2017 August 21 - The earth's umbral shadow crosses USA.

The annular eclipses of 2019 December 26 and 2031 May 21 cross over the South India.

Lunar Eclipses:
2009 December 31 - Penumbral, visible from east Africa, Asia and Australia.
2010 June 26 - Partial, visible from Australia and Pacific.
2010 December 21 - Total, visible from over the north America and the Pacific Ocean.
2011 June 15 - Total, visible from Africa, Asia, Australia and Antarctica.
2011 December 10 - Total, visible from east Asia, Australia and over the Pacific.

The current season is a series of 3 eclipses with 2 penumbral lunar eclipses that occurs on July 7, 2009 and August 6, 2009. These two penumbral lunar eclipses are negligible as only a small portion of the moon passes over the Earth's penumbra, to make only a small portion of the moon to become very slightly dimmer.

Technically, eclipse season is a period of 37 days over which eclipses can occur, when the moon is close enough to the plane of the Earth's orbit around the Sun (the ecliptic). During the other times, the moon is either too above or too below to the ecliptic. If such 3 eclipses occur consecutively over a row, then they must be total or annular solar eclipse within the center, the other two being penumbral lunar eclipses, or that total lunar eclipse within the center, the other two are partial solar eclipses.
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Last fiddled with by Raman on 2009-07-21 at 19:32
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