July 27, 2018 Lunar Eclipse / Blood Moon

A total lunar eclipse will occur on July 27, 2018. The Moon will pass through the centre of the Earth's shadow. This will be the first central lunar eclipse since June 15, 2011.

Since it will occur near apogee, this eclipse will also be the longest total lunar eclipse in the 21st century. Totality will last approximately 103 minutes.

This eclipse will be the second total lunar eclipse in 2018, after the one in January.

It will be completely visible over Eastern Africa, and Central Asia, seen rising over South America, Western Africa, and Europe, and setting over Eastern Asia, and Australia.

Source

A lunar eclipse occurs when the Moon passes within Earth's umbra (shadow). As the eclipse begins, Earth's shadow first darkens the Moon slightly.

Then, the shadow begins to "cover" part of the Moon, turning it a dark red-brown color (typically – the color can vary based on atmospheric conditions).

The Moon appears to be reddish because of Rayleigh scattering (the same effect that causes sunsets to appear reddish) and the refraction of that light by Earth's atmosphere into its umbra.

The following simulation shows the approximate appearance of the Moon passing through Earth's shadow. The Moon's brightness is exaggerated within the umbral shadow. The northern portion of the Moon was closest to the center of the shadow, making it darkest, and most red in appearance.

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By Tomruen

Source / Image Courtesy

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By SockPuppetForTomruen at English Wikipedia

View of Earth from Moon at greatest eclipse.

It will be completely visible over Eastern Africa, and Central Asia, seen rising over South America, Western Africa, and Europe, and setting over Eastern Asia, and Australia.

Source / Image Courtesy

Dragon wrote:The Moon appears to be reddish because of Rayleigh scattering (the same effect that causes sunsets to appear reddish) and the refraction of that light by Earth's atmosphere into its umbra.

Good to know, puzzled me why it appears red, thanks for explaining.

The longest "Blood Moon" eclipse this century will coincide with Mars' closest approach in 15 years to offer skygazers a thrilling astronomical double bill on Friday, astronomers say.

For about half the world, the moon will be partly or fully in Earth's shadow from 1714 to 2328 GMT—six hours and 14 minutes in all.

"Totality will last for 103 minutes, making it the longest eclipse of the 21st century!" said the Royal Astronomical Society in London.

At the same time, Mars will hover near the moon in the night sky, easily visible with the naked eye.

Our neighbouring planet will appear unusually large and bright, a mere 57.7 million kilometres (35.9 million miles) from Earth on its elliptical orbit around the sun.

"We have a rare and interesting conjunction of phenomena," Pascal Descamps, an astronomer with the Paris Observatory, told AFP.

"We should have a coppery red tint on the moon with Mars the 'Red Planet' just next to it, very bright and with a slight orange hue itself."

The long duration of this eclipse is partly due to the fact that the moon will make a near-central passage through Earth's umbra—the darkest, most central part of the shadow.