Prince Philip, the 90-year-old husband of Queen Elizabeth II, resumed official duties on Tuesday evening for the first time since undergoing heart surgery over Christmas.
The Duke of Edinburgh, as he is officially known, looked relaxed as he arrived for a dinner at Cambridge University to mark 100 years to the day since explorer Captain Robert Scott reached the South Pole.
Adventurer Ranulph Fiennes and Prince Albert of Monaco were also among the 100 guests attending the event at Corpus Christi College to raise funds for the Scott Polar Research Institute.
Prince Philip was admitted to hospital on December 23 after complaining of chest pains, and was found to have a blocked coronary artery. He underwent surgery to have a stent fitted, before being released on December 27.
The health scare was the most serious yet for the prince, the longest serving royal consort in British history, and came as the queen prepares to celebrate her diamond jubilee year marking 60 years on the throne.