Stonehenge is famously aligned with the sunrise on the summer solstice and sunset on the winter solstice, yet archaeologists suspect that the Neolithic monument may also have been designed to capture the lunistices, otherwise known as lunar standstills. In particular, the major lunar standstill – which is next due to occur in January 2025 – seems to have had an influence over the layout of the iconic ancient landmark.
Taking place once every 18.6 years, a major lunar standstill marks the point at which the Moon reaches its northernmost and southernmost points in the sky. Over the course of every month, the Moon travels from north to south, yet the extent of this range is in constant flux thanks to the angle of the lunar orbit.
At the peak of its cycle, the Moon’s declination swings from 28.72 degrees north to 28.72 degrees south in a single month. Conversely, during the minor lunar standstill, this celestial motion ranges between 18.13 degrees north and south.
Arguments for Stonehenge’s association with these lunar cycles are currently unresolved, although it has been noted that at least one of the site’s four Station Stones – which surround the inner Sarsen circle – is aligned with the southernmost moonrise during the major lunar standstill. However, archaeologists are unsure of the significance of this feature.
Given the rarity of the event, researchers are keen to take advantage of the upcoming lunistice and are set to begin a series of investigations into the possible alignment of Stonehenge with the Moon’s most extreme rising and setting positions.
Professor Clive Ruggles, who is taking part in the research, explained in a statement that “Stonehenge’s architectural connection to the Sun is well known, but its link with the Moon is less well understood. The four Station Stones align with the Moon’s extreme positions, and researchers have debated for years whether this was deliberate, and—if so—how this was achieved and what might have been its purpose.”
Despite the fact that the lunistice technically lasts for just one month, we are already very much in standstill season, as the Moon is currently reaching declinations further north and south than the solar extremes. According to English Heritage, this period of the lunar cycle may have been interpreted by ancient cultures as the Moon deity becoming more powerful than the Sun god, and might have inspired celebrations, rituals, and other significant events.
Of course, such theories are currently just speculation, but the researchers hope to find some solid clues regarding the prehistoric monument’s relationship with the major lunar standstill early next year.
“We’re excited to be working with a brilliant team of archaeoastronomers to explore the fascinating link between Stonehenge and the major lunar standstill,” said Jennifer Wexler, English Heritage historian for Stonehenge. “Rarer even than once in a blue moon, this opportunity allows us to delve deeper into the monument’s ancient mysteries and its relationship with celestial phenomena.”