solstice

It is composed of sarsens and bluestones, all of them aligned towards the sunrise on the summer solstice and sunset on the winter solstice.

By comparison, in the astronomical calendar, winter always starts at the winter solstice - or shortest day.

By 21 December, the Sun will have reached its lowest point in the sky during the day, marking the winter solstice.

The swim, on the date of the first "supermoon" of the year, was inspired by the dawn solstice swims that have taken place at the lido in June for the past 10 years.

“It’s rising farther south than the winter solstice sun,” Vanessa Alarcon, the astronomical observer at the Griffith Observatory, told The Times last week.