Greek philosopher Heraclitus of Ephesus bequeathed to us this bit of wisdom: “No man ever steps in the same river twice, for it’s not the same river and he’s not the same man.” 

Heraclitus was on to something. I feel the same way about many of my recurring experiences in nature. Can one ever get tired of a sunset or waterfall?

How about a lunar eclipse? That periodic feat of nature is headed our way next week, and it brings curiosity, beauty and wonder yet again. If they came every night, I would still be fascinated.

We were privy to one last April, and we will be graced with another next week. In 2014, there will be two total lunar eclipses, with two more to follow in 2015. A total of four consecutively is called a tetrad and the next tetrad won’t happen until 2032!

No matter how wonderful it could be, a nightly appearance of a lunar eclipse is impossible. It is only during the full moon that this special event can occur. A total lunar eclipse has been called a “freak of cosmic happenstance,” occurring only when the sun, earth and moon line up, so that the earth’s shadow blocks the sun’s light. 

An early explanation of this celestial event was put forth by another Greek philosopher named Anaxagoras. A historian penned his explanation, “Anaxagoras, in agreement with the mathematicians, held that the moon’s obscurations (phases), month by month, were due to its following the course of the sun by which it is illuminated, and that the eclipses of the moon were caused by its falling within the shadow of the earth, which then comes between the sun and the moon, while the eclipses of the sun where due to the interposition of the moon.” Keep in mind that this was centuries before Copernicus proposed the heliocentric model of the solar system.

Anaxagoras, by the way, was exiled from Athens in 435 B.C. for daring to suggest that the sun was not just a light in the sky, but might be a glowing rock a hundred miles across.

While lunar eclipses do happen periodically, they are not common. In fact, the irregularity of lunar eclipses can sometimes cause distress. In the Greek region of Thessaly, witches claimed that they were able to extinguish the moon’s light and draw it down from the sky.

Isaac Asimov wrote: “Total eclipses of the moon are considerably rarer than total eclipses of the sun. However, a total eclipse of the moon can be seen from anywhere on the side of the Earth facing the moon. A total eclipse of the sun can only be seen from a narrow band about a hundred miles wide at the most. The person who doesn’t travel is sure to see a far greater number of lunar eclipses than solar eclipses.”

Aristophanes used its occurrence in his comedy, but it still sounded disconcerting, “the moon deserted her course and the sun at once veiled his beam, threatening, no longer to give you light.”

Shakespeare was so captivated by eclipses that he referred to them in his sonnets, as well as in some of his best plays — King Lear, Macbeth, Hamlet and Othello.

If the weather (and clouds) cooperate, we might be able to see this week’s eclipse. It should take about three hours to go through the entire eclipse, beginning in the early morning hours. Even if you miss part of it, at least take note of the moon, because it might be an amazing red color, caused by the scattering of light of the other colors of the spectrum.

The coming Hunter’s moon and its total eclipse brings more than just a notice to prepare for the change of seasons. It brings history, science, serendipity and rarity to remind us to look above to the sky and marvel at it once again.

Suzan Bellincampi is director of the Felix Neck Wildlife Sanctuary in Edgartown, and author of Martha’s Vineyard: A Field Guide to Island Nature.