When our only natural satellite rises at 4:58 pm this evening it will be only a few hours past its “supermoon” position. The name given to the phenomenon by astronomers is the “perigee-syzygy of the Earth-Sun-Moon system,” which is less poetic than supermoon, a term coined by astrologer Richard Nolle in 1979.
The moon’s orbit is slightly elliptical (ovoid) and its distance from the Earth varies between 222,000 (perigee) and 252,000 (apogee) miles. Nolle decided that the moon was super if its orbit was within 10 percent of the perigee. The last time this happened was Sept. 28, 2015. Although the moon was not quite as close as it is now, the event was accompanied by a lunar eclipse.
The syzygy portion of the scientific term for this event refers to the fact that the Earth is directly between the Moon and the Sun, as it is for every full moon. This configuration, which also occurs at the new moon, when the Moon is between the Earth and the Sun, causes “spring tides,” which are both higher and lower than average. The gravitational pull of the Sun is 46 percent that of the Moon. When the celestial bodies are aligned, the forces have a cumulative effect. During a supermoon event the closeness of the Moon further enhances the combined gravitational pull on the oceans.
According to CapeCodWeather.net, the highest tides in the region are expected on Tuesday and Wednesday, Nov. 15 and 16. High tide at Vineyard Haven is at 11:30 a.m. on Nov. 15 and 12:08 p.m. on Nov. 16.
The next time the moon will be as close as it is this evening will be Nov. 25, 2034, when hopefully, we will have stopped arguing about electoral votes.
On Martha’s Vineyard, head to east-facing spots, such as West or East Chop (facing the Cape), the Inkwell in Oak Bluffs (or the nearby seawall by Farm Pond), big or little bridges, Fuller Street Beach in Edgartown, or Cape Pogue on Chappy.
If you miss it tonight, even the setting moon, around 5:45 am on Tuesday, may make you catch your breath. This morning, Islanders reported seeing the big yellow moon setting over the town of Vineyard Haven as they headed for an early boat.
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