The Australian Post has issued two stamps in honor of the Queen's Official Birthday.
This is not Queen Elizabeth's actual birthday, which is April 21st. The Official Birthday is held sometime in June, but it varies from country to country in the Commonwealth of Nations. This second birthday first appeared in the beginning of the 20th Century when Edward VII chose to celebrate his November birthday in the Summer.
The 2009 Queen's birthday stamp issue features the Trooping of the Colour parade, which marks the Queen's official birthday each year.
The stamps in this year's issue show how the Queen has participated in the parade during her reign; from riding at the head of the parade in regimental uniform to riding in a carriage.
The miniature sheet features the annual Trooping of the Queen's Colour in Australia held at the Royal Military College of Australia, Duntroon in Canberra.