His Majesty pays tribute to Antarctic researchers as they mark South Pole’s coldest day of the year

King Charles is the first monarch to take part in the annual BBC broadcast, which sends a morale-raising message to scientists on remote research bases.

While the UK enjoys its longest day of sunlight on Saturday, British scientists at the South Pole experience 24 hours of darkness.

His Majesty pays tribute to Antarctic researchers as they mark South Pole’s coldest day of the year