Friday lunar eclipse to be the longest in 21st Century

Total lunar eclipse darkens the moon giving it a reddish colour. [Courtesy]

On Friday July 27, 2018, sky watchers at Omenyangamong in Turkana, Kenya will witness the longest total lunar eclipse of the 21stcentury, space science source has revealed.

According to the geographical website timeanddate.com, the eclipse will start at 20:14 (8.14pm) then last for 103 minutes making it the longest in this century.

Lunar eclipse can occur only during a full moon and this time round, the moon will be perfectly aligned with the Sun and Earth.   

According to the timeanddate.com timetable the skies will be darkest at 23:21.

The Eclipse will end on Saturday July 28, 2018 at around 02:28.

The timeanddate.com explains that penumbral lunar eclipse occurs when the Moon passes through Earth's penumbra. The penumbra causes a subtle dimming of the lunar surface. A special type of penumbral eclipse is a total penumbral lunar eclipse, during which the Moon lies exclusively within Earth's penumbra.

Total penumbral eclipses are rare, and when these occur, the portion of the Moon closest to the umbra may appear slightly darker than the rest of the lunar disk.

The website further states that partial lunar eclipse occurs when only a portion of the Moon enters Earth's umbra, while a total lunar eclipse occurs when the entire Moon enters the planet's umbra.

Adds the website “The Moon's average orbital speed is about 2,300 mph (1.03 km/s), or a little more than its diameter per hour, so totality may last up to nearly 107 minutes. Nevertheless, the total time between the first and the last contacts of the Moon's limb with Earth's shadow is much longer and could last up to four hours.”

Stages and times (local times, EAT) of the eclipse at Omenyangamong in Turkana County. [ Courtesy]

According to a report by CNN the lunar eclipse will also reveal a ‘Blood Moon’. This refers to the phenomenon where the moon appears reddish as it is illuminated by sunlight filtered and refracted by the earth's atmosphere, explains CNN.

The report also states that the Earth will cast two shadows on the Moon during the eclipses. The penumbra is the partial outer shadow, and the umbra is the full, dark shadow.

When the full moon moves into Earth's shadow, it will darken, but it won't disappear, CNN explains further.

“Sunlight passing through Earth's atmosphere will light the moon in a dramatic fashion, turning it red hence forming the Blood Moon.”

This global event will be experienced in most parts of the world and will be viewed in large parts of Australia, Asia, Africa, Europe, and South America, according to the cable TV network.

On January 31, 2018 Nairobi was one of the viewpoints for around the world for the Penumbral Eclipse, which was experienced as from 6.53pm to 7.08pm East African Time.

The 15 minute event took place under various conditions.

That kind of lunar eclipse is known as the 'super blue blood moon'.