LONDON: Thousands have watched the sun glint over the horizon at Stonehenge, celebrating the summer solstice at the Neolithic stone circle.

The sun rose behind the Heel Stone, which traditionally marks the spot on the horizon for the sunrise, at 4.52am on Thursday.

Crowds cheered and raised mobile phones for images as the rays flooded through the monument and announced the longest day of the year in the Northern Hemisphere.

English Heritage, which cares for historic sites, tweeted that it was the “perfect morning for the #SummerSolstice sunrise at Stonehenge.” The stone circle in southern England, believed to be 4,500 years old, is a World Heritage site known for its alignment with the movements of the sun. Thousands visit to mark the solstices in summer and winter.

Scientists based in Antarctica welcomed the winter solstice by plunging into icy waters as part of a “mad tradition” heralding the return of brighter days after weeks of darkness.

In temperatures of -22 degrees Celsius, staff at Australia’s Casey research station marked midwinter’s day by cutting a small pool in the thick ice before stripping off and jumping in.

Casey station leader Rebecca Jeffcoat said midwinter day — the shortest of the year — was the most anticipated occasion on the Antarctic calendar and has been celebrated from the time of the early explorers.

“Swimming in Antarctica’s below freezing waters is something of a mad tradition, but our hardy expeditioners look forward to it, with 21 of the 26 people on station brave enough to take an icy dip this year,” she said.

“Midwinter day is really important in Antarctica because it marks the halfway point of our year here on the ice and it means the sun will spend slightly longer in the sky each day.”

Published in Dawn, June 22nd, 2018