Blood Moon

Rare Celestial Event: The Super Blue Blood Moon

Of all the many eye-catching astronomical events occurred till date, 2017 seems to be the best remembered for the much anticipated total eclipse of the Sun. Last January 31st, 2018 happened to grab the curiosity of skywatchers which showcased another rare celestial event when a blue moon and lunar eclipse combined and resulted in a “super blue blood moon”.

The “super blue blood moon” is a combination of three different planetary events: the blue moon (blue color because of the dust or smoke particles of specific sizes present in air scatters the blue light), the supermoon or perigee (is the point at which the Moon is closest in its orbit to the Earth), and the total eclipse (Earth comes between the Sun and the Moon and covers the Moon with its shadow). But the reason it turns into reddish is due to “the effect of all the sunrises and sunsets all around the planet reflecting off the moon”, said NASA astrophysicist Michelle Thaller. A “blue moon” happens on an average of three years or less. So, what makes this year so special? Because, this year’s supermoon or perigee, makes the super moon appear 14 percent bigger than normal and 30 percent brighter.

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The paraxial view of a lunar eclipse, showing the Earth passes between the sun and the moon and our planet’s shadow falls on Luna. (Credit: MICHAEL STILLWELL)

NASA said the occurrence of this rare eclipse offered scientists a chance to see what happens when the surface of the moon cools quickly. “The whole character of the moon changes when we observe with a thermal camera during an eclipse,” said Paul Hayne of the Laboratory for Atmospheric and Space Physics at the University of Colorado Boulder. “In the dark, many familiar craters and other features can’t be seen, and the normally nondescript areas around some craters start to ‘glow’ because the rocks found there are still warm.”

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Stages of the Jan. 31, 2018 “super blue blood moon” are depicted in Pacific Time with “moonset” times for major cities across the U.S., which affect how much of the event viewers will see. (Credit: NASA)

Referring to the stages for the occurrence of total lunar eclipse, can be categorized into two states viz. Umbra and Penumbra. The total lunar eclipse occurs when the moon is completely submerged in Earth’s dark, inner shadow, called the umbra. If the moon is only partly covered by the umbra, or only enters the outer shadow it is called as the penumbra and is considered as a partial lunar eclipse. The total eclipse is said to “begin” when the moon is fully covered by the umbra; this phase is called as “totality.”

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The Moon’s orbit is not a perfect circle. When perigee coincides in a full thrust, we achieve a Supermoon. (Credit: Brian Koberlein)

The rareness of the eclipse in 31st Jan 2018 is completely arbitrary, but the sight of a big, red, eclipsed Moon is something people should not miss. The mankind always aspires to get such opportunities in their life. So people naturally showed enthusiasm over the event all over the world. Although, the next super blue blood moon will happen on December 31, 2028, but won’t be quite as large since the moon will not be at its closest point to Earth.

Sources: Space, theguardian, Forbes, BGR

A research patron working in the field of Plasma and Nuclear Science. He prefers the hobby in writing scientific prologs and keeps a strong feeling in mind to promote knowledge by holding technology in hand.