Once in a Blue Moon

This month was a rear Luna event, two Super Full Moons within the month of August, which means it was a “Blue Moon - Super Moon”. This week Super Full Moon was on 30, 31 August 2023 and at the beginning of the month on 2 August 2023 was the first Full Moon.

Many residents on Norfolk Island will remember the last Super Full Moon, which was when the Military Talisman Sabre training exercise took place on Norfolk Island and the military planes had a busy night as they flew around our remote island “all night long” and using the full moon to identify landmarks of Norfolk Island.

I read that the Blue Super Moon last occurred in 2009. This month is the final of this year’s Super Moons and the next Super Full Moon until 18 September 2024.

The term Super Moon describes the full moon coinciding with the closest point in its orbit around the earth, or known as in perigee. Super Moons are brighter than the average full moon.

The term Blue Moon describes the frequency of Full Moons, as an extra Full Moon in a calendar year, or two full moons in the same month. The moon does not turn blue, it is a term which describes the event.

It was interesting to read that this month’s New Moon on 16 August 2023 was named a Micro New Moon, which is when the moon coincides with apogee, the point in the moon’s orbit farthest away from the Earth.

The point on the Moon's orbit closest to Earth is called the perigee

and the point farthest away is the apogee.

This link has many interesting details about astronomical and the moon events.

https://www.timeanddate.com/moon/phases/norfolk-island/kingston

Why Is It Called a Blue Moon?

The historical origins of the term and its two definitions are shrouded in a bit of mystery and, by many accounts, an interpretation error.

Some believe that the term “blue moon” meaning something rare may have originated from when smoke and ashes after a volcanic eruption turned the Moon blue. Others trace the term's origin to over 400 years ago—folklorist Philip Hiscock has suggested that invoking the Blue Moon once meant that something was absurd and would never happen.

Origins of the Monthly Blue Moon

The more popular definition of the Blue Moon, that of the second Full Moon in a month, owes its existence to a misinterpretation originally made by amateur astronomer James Hugh Pruett (1886–1955) in a 1946 edition of Sky & Telescope magazine. The error took on a life of its own and spread around as fact. It even found its way into the answers of the 1986 version of the board game Trivial Pursuit! Today, this definition is considered a second definition of the Blue Moon rather than a mistake.

Another interesting effect of Super Moon events is spring tides or higher tides. It is interesting at Kingston to walk the shoreline and view the reef areas around the Kingston Pier and the historic course-way which was first constructed as steppingstones from shore to the inner reef after the wreck of HMS Sirius in 1790.

Higher Tides at Supermoon

The greatest difference between high and low tide is around Full Moon and New Moon. During these Moon phases, the gravitational forces of the Moon and the Sun combine to pull the ocean’s water in the same direction. These tides are known as spring tides or king tides.

Supermoons lead to around 5 cm (2 inches) larger variation than regular spring tides, called perigean spring tides.

The tidal range is smallest during the two Quarter Moons, known as neaps or neap tide.

I enjoy our Norfolk Island magical dark skies, and it is always interesting learning about the astronomical events. During the Super Full Moon, the nights will be bright as the Luna light reflects off the ocean, the seawater acting like a mirror, but this can also cast shadows and light up trees and historic areas, which can make nighttime photography interesting. The starry nights are so amazing, just remember to wrap up warm and step outside and look up and be overwhelmed by the view. The winter nights are great for astrophotography, it is always rewarding to capture the night skies above Kingston and along the lagoon.

This month I captured images of the full moon at the beginning of the month during the military and air-force training night, and again this week, I captured some moon photos up Mt Pitt during clear skies on Tuesday sunset, when the moon was 96% Full.

Hope you all enjoy this month’s Super Blue Full Moon.

Betty Matthews

September 2023