A rare lunar event may reveal Stonehenge’s connection to the moon

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To those who have gathered over the centuries in Stonehenge — The majestic prehistoric monument It has dominated the Salisbury Plain in southwest England for about 4,500 years, and it is probably clear how the sun could have determined its design.

The central axis of the stone circle was, and still is, aligned with midsummer sunrise and midwinter sunset, with the stones dramatically framing the sunrise and sunset when the days are longest and shortest.

But do Stonehenge and other possible megalithic monuments around the world also correspond to the Moon?

The idea that Stonehenge was somehow connected to the moon It acquired the land in the 1960s. However, this concept has not been systematically explored, said Clive Ruggles, emeritus professor of archaeoastronomy at the University of Leicester’s School of Archeology and Ancient History.

This summer archaeologists are using a little-known lunar phenomenon that occurs every 18.6 years to investigate as part of their work in understanding why Stonehenge was built.

The moon stopped

Like the sun, the moon rises in the east and sets in the west. However, the moonrise and sunset move from north to south and back again within a month. The north and south ends also change over a period of about 18 and a half years. A lunar stop occurs when the rising and setting of the moon are farther north and farther south than each other.

Fabio Silva, senior lecturer in archaeological modeling at Bournemouth University, said: “The height of the moon changes every day, and if you track that for a month you will notice that there is a north-south boundary beyond which the moon never rises (or sets). University via email.

“If you look at these boundaries over the course of 19 years, you will notice that they change like an accordion: they expand to a maximum (the major lunar pause) and then begin to contract to a minimum (the minor lunar pause).” “.

This major lunar pause is scheduled to occur in January 2025, but between now and mid-2025, to a casual observer, the Moon may appear unusually low and high in the night sky during the lunar month.

“If you’re in one of those 19 years, from time to time, you’ll see the moon rise or set much further north or south than it does most of the time. In the intervening years, you never see it there,” Ruggles said.

He said that despite the name of the phenomenon, the moon does not stand still during this period.

“What stands still are these boundaries, “The moment that happens will be in January of next year,” Ruggles added. “But for about a year on either side, if you happen to catch the moonrise at the right time, you will see the moon rising exceptionally low (in the sky).”

Stonehenge consists of two types of stone: larger sarsen stones and smaller bluestones that form two concentric circles. The Stonehenge station stones, which form a rectangle around the circle, roughly align with the moon’s maximum positions during the moon’s cessation, Ruggles said.

How this lunar alignment was achieved, whether by design and its possible purpose, are topics of discussion that the team wants to investigate.

Although there are no written documents that shed light on the meaning and importance of Stonehenge, archaeologists have long believed that the alignment of the sun was intentional. Such alignments have been identified in many places around the world, and were relatively easy for ancient builders to determine, since knowledge of the sun’s annual cycle and its connection with the seasons was essential to making a living.

However, it is very difficult to determine whether Stonehenge actually had anything to do with the lunar pause.

“I don’t think we can say definitively, but to me, there is some evidence that makes me believe it was intentional,” Ruggles said.

One clue was the fact that archaeologists found cremated human remains clustered in the southeast, near where the southernmost moonrise would occur.

“I think there’s a possibility that they knew about this orientation of the moon and then that became some kind of sacred orientation,” Ruggles said.

Since April, Ruggles and Silva, along with colleagues from Bournemouth University, Oxford University and English Heritage, the organization that runs the site, have been documenting moonrises and sunsets at key moments when the moon is aligned with the station stones. The moon is expected to align with the station’s stone rectangle twice a month from about February 2024 to November 2025, Silva said.

“This will happen at different times of the day and night throughout the year, with the moon being in the right place at different phases each month,” Silva said. Press release in April.

The team wants to understand the patterns of light and shadow that the moon creates at Stonehenge and whether they could hold meaning for the people who built and used the monument.

Stonehenge is not the only megalithic monument potentially linked to the lunar pause.

In the United States, Erica Ellingson, professor emeritus of astrophysics at the University of Colorado Boulder, is studying the Moon’s alignment at Chimney Rock, a rocky ridge that rises about 1,000 feet above the valley floor in Colorado. The landmark features two large pillar-like rocks that form the skyline.

Between 900 and 1150, the ancestors of the Pueblo people built multi-story buildings and ritual places on this high, inaccessible place that has a dramatic view and remains an important site for the nation’s 26 Native American groups, Ellington said. Which have traditional or cultural ties to the region.

“The extraordinary view of the sky between the twin peaks suggests an astronomical connection, but the gap is a little too far north for the sun to shine through. However, the moon can be seen rising there when it is close to its northernmost position, during the main lunar pause season.” .

She added that additional evidence of moon observations comes from tree rings dating to wooden beams in ancient buildings nearby, suggesting that their construction is linked to the dates when the moon ceased nearly 1,000 years ago.

Ruggles said the Calanniye Standing Stones, located on the Isle of Lewis in Scotland and erected before Stonehenge, may also have a connection to the lunar pause.

Bradley Schaeffer, a professor emeritus in the Department of Physics and Astronomy at Louisiana State University, said he was very skeptical that the ancients knew about the lunar cessation and built monuments consistent with it. He pointed out that it was most likely a coincidence.

“Each ancient site has dozens to hundreds of potential sight lines, and one or more will always point somewhere near one of the eight stopping directions,” he said via email.

He added that it is difficult for any ordinary moon observer to recognize the state of the moon’s cessation, and it can only be seen in detailed data about moonrise and sunset observations.

While the shift in the moon’s position is subtle and historical records documenting the moon’s cessation are rare and difficult to interpret, Ellington said she believes the connection is plausible because many ancients viewed the sky up close.

“A moon observer would have seen the moon begin to rise or set outside these boundaries, and move farther and farther out of bounds as the main lunar pause approached,” she said.