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A Blood Moon

26 July 2018   (0 Comments)
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A lunar eclipse will be visible over much of the Earth on 27 July

Most of the Eastern Hemisphere will see part or all of the eclipse - and the entire event will be visible from Africa, the Middle East and Central Asia.

The time of greatest eclipse will be 2021 UTC (2121 BST) on 27 July. Total eclipse - with the moon in the Earth’s full shadow (umbra) will last from 1930 to 2113 UTC (2030 to 2213 BST). There will also be some time before and after when the moon is in the half-shadow (penumbra). Including penumbral time, the eclipse will last for 3h 55m.

The moon will be at its greatest distance from Earth in its elliptical orbit - hence it will appear smaller than usual and the eclipse will last longer than normal. The next lunar eclipse of this length will not occur until 9 June 2123.

Any sunlight that does reach the Moon during the eclipse has to pass through the Earth’s atmosphere, where the longer-wavelength red end of the spectrum penetrates better than the shorter-wavelengths towards violet, which get scattered.  Hence the Moon will appear red - a ‘Blood Moon’.

The lunar eclipse coincides with Mars being at its closest point to Earth for 15 years; it should be seen a little lower and to the right of the Moon.

Cloud permitting, the eclipse should be visible from the UK although, with moonrise in London at 2049 BST, the beginning will be missed.

Details from