The Black Moon Supermoon combo will arrive tomorrow (August 30) with the New Moon phase of the lunar cycle. A Black Moon is an incredibly rare occurrence by some definitions and only makes an appearance once every five to 10 years. A New Moon, on the other hand, marks the start and end of the monthly lunar cycle when the Moon is shrouded in complete darkness. Read on below to learn more about tomorrow’s astronomical spectacle.
What is a Black Moon?
A Black Moon is not a scientifically defined term and there are many loose definitions used by amateur astronomers.
Tomorrow’s Black Moon is the result of a Supermoon – closest lunar approach – falling on the same day as a New Moon.
The Old Farmer’s Almanac said: “Like ‘Blood Moon’ and ‘Blue Moon’, ‘Black Moon’ is not an astronomical term.
“In fact, if you ask a sample of astronomers, both professional and amateur, very few will have even heard of it.
“It’s not even a particularly widely known folklore thing.”
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By one definition, a Black Moon is the second of two New Moons to fall in a calendar month.
Another definition describes a Black Moon as no New Moon in a month.
Sometimes a regular New Moon is also known as a Black Moon because the lunar phase is not visible to the naked eye.
The Old Farmer’s Almanac said the Black Moon can also be the third of four New Moons to appear in a single season.
By this same definition, a Blue Moon appears if it happens to be a Full Moon instead.
What is a Supermoon?
When the Full Moon or New Moon approaches its nearest orbital distance from our planet, astronomers refer to it as a Supermoon.
The term is loosely defined as a Moon within 10 percent of its point of perigee.
If the Moon as its farthest point, the apogee, it is sometimes referred to as the Micromoon.
During a Full Supermoon, the lunar orb appears slightly bigger and brighter to seasoned astronomers.
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US space agency NASA said: “The Moon orbits Earth in an ellipse, an oval that brings it closer to and farther from Earth as it goes around.
“The farthest point in this ellipse is called the apogee and is about 253,000 miles (405,500km) from Earth on average.
“It’s closest point is the perigee, which is an average distance of about 226,000 miles (363,300km) from Earth.
“When a Full Moon appears at perigee it is slightly brighter and larger than a regular Full Moon – and that’s where we get a ‘Supermoon’.
The term Supermoon is believed to have been coined in 1979
