Public gathering celebrates our longest day of the year

Some call it the first day of summer, but in reality, it’s the beginning of our long march to winter. It’s hard to believe, but the days are about to start getting shorter following the Summer Solstice and the longest day of the year on June 21.

On that day, the sun sets at its northernmost point on the horizon. To observe the event, a gathering will take place at the Pen Henge standing stone array on the top of Munson Mountain in Penticton on Thursday from 8-9 p.m.

The public gathering is being organized by the Okanagan Centre of the Royal Astronomical Society of Canada, with the assistance of radio astronomer Chris Purton.

At approximately 8:50 p.m., the sun will set over the mountains to our west, and if clear, the last rays of the sun will cast a shadow from the northernmost or “Summer Solstice” stone toward the central Heel Stone at the back of the standing stone array.

As determined from previous careful readings at Pen Henge, the local sunset will take place at approximately 8:50 pm that evening. The actual time of the solstice this year will occur Thursday at 3:07 a.m.

Pen Henge is a project that was spearheaded by Purton, who is a retired radio astronomer at the Dominion Radio Astrophysical Observatory at White Lake.

The installation, which is located at the top of Munson Mountain, above the large “Penticton” sign on the east side of Okanagan Lake, consists of four stones that delineate the sunset points on the four cardinal dates of the year.

Anchored by the Heel Stone, the Equinox Stone points to the Sun’s sunset point at both the Spring and Fall Equinoxes, while the other two stones at the southern and northern limits of the Sun’s range, mark the Winter and Summer Solstice setting points respectively.

A brass plaque with a brief explanation of the array is permanently attached to the top of the heel stone at the top of Munson Mountain.