Many people consider Dec. 21 as the first day of winter.

In actuality, even though it is the longest night of the year, it marks the beginning of the return of the sun, with the start of ever-increasing longer days until summer solstice in June.

The public is invited to renew the ancient custom of welcoming back thee Sun, observing the annual winter solstice as the Okanagan鈥檚 Penhenge, a standing stone array on Munson Mountain in Penticton.

The annual event, which marks the Sun鈥檚 southernmost setting point of the year, will take place on Thursday afternoon, Dec. 21, with people gathering around 2:45 p.m. in anticipation of a presentation around 3:10 p.m. and sunset at 3:27 p.m.

The actual time of the solstice will occur at 7:27 p.m., long after the gathering has dispersed.

Penhenge designer Chris Purton, a retired scientist at the Dominion Radio Astrophysical Observatory at White Lake, will explain the significance of the event.

Participants will be able to observe the sunset phenomenon as the rays of the setting sun extend from the winter solstice stone to the heel stone of the stone array.

The gathering is being organized by thee Penticton meeting group of the. Okanagan Centre of the Royal Astronomical Society of Canada and members will be on hand to answer questions as well as describe the significance of what is taking place.

The organizers remind guests to dress warmly and wear good footwear since there may be ice at the top of the hill. Parking may be limited so some may have to park below on Munson Mountain Road.

At our latitude, Solstice Day will have only eight hours and nine minutes of daylight and almost 16 hours of night.

As of Dec. 22, the daylight hours will start to grow longer each day until summer solstice on June 20, 2024.

The Penhenge standing stone array is located at the top of Munson Mountain above the large Penticton sign on the east side of Okanagan Lake. The array 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鈥檚 sunset point at both the spring and fall equinoxes, while the other two stones mark the winter and summer solstice stetting points respectively.

鈥淔or most of the year, the structure simply illustrates the enormous range along the western horizon where the Sun sets,鈥� Purton says. 鈥淢ost people subconsciously know this, but they are quite fascinated to see the idea laid out so graphically.鈥�

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