Thursday, 1 September 2016

Why Eclipse Was Hard To Observe in Nigeria

The observation of the Partial Solar Eclipse proved somewhat difficult as the occurrence was similar to the gathering of cloud before a downpour.

Correspondents observing the eclipse in Igbogbo area of Ikorodu, Lagos reports that the highest point of the occurrence was around 8.00 am to 8:45 am , when the cloud was very thick.

But it started around 7:15am with the emission of  a very sparkling radiation coming out of a dim sky.

Around 8 to 8:45 am, it became very cloudy, accompanied by light thunderstorm. That could be the highest point of the eclipse.

The cloudy atmosphere vanished around 8:50 am, back to the the emission of sparkling radiation , as it was when it started.

It will be recalled that a geographer, Dr. Nasiru Idris , of the Nasarawa State University, Keffi had told Radio Nigeria that due to the cloudy weather as a result of rainfall in the country, Nigerians would not be able to clearly see the eclipse.

Watch the short video clips of the eclipse as observed by correspondents in Igbogbo, Ikorodu.




Theory
From Wikipedia:

Geometry of full solar eclipse
As seen from the Earth, a solar eclipse is a type of eclipse that occurs when the Moon passes between the Sun and Earth, and the Moon fully or partially blocks ("occults") the Sun. This can happen only at new moon, when the Sun and the Moon are in conjunction as seen from Earth in an alignment referred to as syzygy. In a total eclipse, the disk of the Sun is fully obscured by the Moon. In partial and annular eclipses, only part of the Sun is obscured.

If the Moon were in a perfectly circular orbit, a little closer to the Earth, and in the same orbital plane, there would be total solar eclipses every month. However, the Moon's orbit is inclined (tilted) at more than 5 degrees to the Earth's orbit around the Sun (see ecliptic), so its shadow at new moon usually misses Earth. 

Earth's orbit is called the ecliptic plane as the Moon's orbit must cross this plane in order for an eclipse (both solar as well as lunar) to occur. In addition, the Moon's actual orbit is elliptical, often taking it far enough away from Earth that its apparent size is not large enough to block the Sun totally. The orbital planes cross each other at a line of nodes resulting in at least two, and up to five, solar eclipses occurring each year; no more than two of which can be total eclipses.

 However, total solar eclipses are rare at any particular location because totality exists only along a narrow path on the Earth's surface traced by the Moon's shadow or umbra.

An eclipse is a natural phenomenon. Nevertheless, in some ancient and modern cultures, solar eclipses have been attributed to supernatural causes or regarded as bad omens. A total solar eclipse can be frightening to people who are unaware of its astronomical explanation, as the Sun seems to disappear during the day and the sky darkens in a matter of minutes.

 
Geometry of all solar eclipses
A partial eclipse occurs when the Sun and Moon are not exactly in line and the Moon only partially obscures the Sun. This phenomenon can usually be seen from a large part of the Earth outside of the track of an annular or total eclipse. However, some eclipses can only be seen as a partial eclipse, because the umbra passes above the Earth's polar regions and never intersects the Earth's surface. Partial eclipses are virtually unnoticeable, as it takes well over 90% coverage to notice any darkening at all. Even at 99% it would be no darker than civil twilight.



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