Japan's Emperor Akihito, left, speaks to the media as Empress Michiko looks on during a news conference at the Imperial Palace in Tokyo on Nov. 6, 2009, marked 20 years on the Japanese throne Nov. 12, 2009 with tens of thousands of well-wishers lining the streets of Tokyo to celebrate.
Well-wishers wave national flags as Emperor Akihito and Empress Michiko make a public appearance during a special event to mark the 20th anniversary of the monarch's coronation to the throne Nov. 12, 2009. A parade, a concert and other events in Tokyo marked the anniversary of Akihito's ascent to the world's oldest hereditary throne.
People in festival costume carry portable shrines through a street in front of the Imperial Palace in Tokyo, during a parade to mark the 20th anniversary of Emperor Akihito's coronation Nov. 12, 2009. Akihito assumed the throne after his father's Jan. 7, 1989, death but was not coronated until the country's mourning period ended.
Emperor Akihito, right, and Empress Michiko, center, are greeted by Prime Minister Yukio Hatoyama as they arrive at the National Theater in Tokyo, for a ceremony in commemoration of the 20th anniversary of the emperor's coronation, Nov. 12, 2009. In remarks at the government-sponsored celebration, Akihito mentioned his contrition over World War II.
Emperor Akihito, center, accompanied by Empress Michiko, right, acknowledges the crowd as attendants shout "Long live the emperor" led by Prime Minister Yukio Hatoyama, left, during a ceremony to mark the 20th anniversary of the monarch's coronation Nov. 12, 2009. Akihito's primary role is that of a figurehead, presiding over rituals, meeting foreign dignitaries and swearing in new Cabinets.
Emperor Akihito and Empress Michiko arrive at the National Theater in Tokyo, for a ceremony in commemoration of the 20th anniversary of the emperor's coronation, Nov. 12, 2009. In a speech, Akihito urged the Japanese not to forget the lessons of World War II.
Japanese Emperor Akihito, right, and Empress Michiko, second from right, receive bouquets of flowers from Girl Scout Kurumi Sasaki, second from left, and Boy Scout Ryotaro Nishimiya at their departure after attending a ceremony in commemoration of the 20th anniversary of the emperor's coronation at the National Theatre in Tokyo, Nov. 12, 2009.
With banners celebrating the 20th anniversary of Emperor Akihito's coronation, people in festival costume carry portable shrines through a street in front of the Imperial Palace in Tokyo, Japan, during a parade to celebrate the anniversary Thursday, Nov. 12, 2009. Over the past 20 years, Akihito and his wife, Empress Michiko, have grown quietly into their roles as ceremonial symbols of the nation.
Japanese Prime Minister Yuikio Hatoyama, right, bows as he sees Empress Michiko, center, and Japanese Emperor Akihito, unseen behind Michiko, off after the couple attended a ceremony in commemoration of the 20th anniversary of the emperor's coronation at the National Theatre in Tokyo, Nov. 12, 2009.
People in festival costume holding Japanese lanterns shout cheers as they lead a float being pulled through a street in front of the Imperial Palace in Tokyo, Japan, during a parade to celebrate the 20th anniversary of Emperor Akihito's coronation Thursday, Nov. 12, 2009.
Well-wishers sign greeting books for the 20th Anniversary of the enthronement of Emperor Akihito at the Imperial Palace in Tokyo Thursday, Nov. 12, 2009. The emperor was enthroned Jan. 7, 1989, following the death of his father Emperor Hirohito.
Well-wishers receive security checks as they arrive at the Imperial Palace compound to sign greeting books for the 20th Anniversary of the enthronement of Emperor Akihito in Tokyo, Japan, Thursday, Nov. 12, 2009.
Japanese Prime Minister Yukio Hatoyama, right, former Prime Ministers, Yasuo Fukuda, left, and Shinzo Abe, second from right, shout "Long live the emperor" as Emperor Akihito and Empress Michiko make a public appearance for well-wishers during a special event to mark the 20th anniversary of the monarch's coronation to the throne at the Imperial Palace in Tokyo, Japan, Thursday, Nov. 12, 2009.
Japanese Emperor Akihito, left, and Empress Michiko wave paper lanterns as they acknowledge well-wishers during a special event to mark the 20th anniversary of the monarch's coronation to the throne at the Imperial Palace in Tokyo, Japan, Thursday, Nov. 12, 2009.
Emperor Akihito, left, and Empress Michiko applaud from a bridge of the Imperial Palace during a special event to celebrate the 20th anniversary of Akihito's coronation Nov. 12, 2009. The 75-year-old monarch has said he is in good health, although he has been treated for cancer and other ailments and appeared frail.
Japanese well-wishers hold paper lanterns and watch Emperor Akihito and Empress Michiko on a screen outside the Imperial Palace grounds in Tokyo, Japan, as the couple make a public appearance during a special event celebrating the 20th anniversary of Akihito's coronation to the world's oldest throne, Nov. 12, 2009.
Japanese well-wishers wave national flags and lanterns in front of the Imperial Palace in Tokyo, Japan, as Emperor Akihito and Empress Michiko make a public appearance during a special event celebrating the 20th anniversary of Akihito's coronation to the world's oldest throne Thursday, Nov. 12, 2009.
Japanese Emperor Akihito, left, and Empress Michiko wave paper lanterns as they acknowledge well-wishers during a special event to mark the 20th anniversary of the monarch's coronation to the throne at the Imperial Palace in Tokyo, Japan, Thursday, Nov. 12, 2009.
Earlier this year, the royal couple marked their 50th wedding anniversary. In this photo released by the Imperial Household Agency of Japan on the day of the wedding, April 10, 1959, then Crown Prince Akihito, left, and his bride, Michiko Shoda, pose in the ceremonial robes they wore during a ceremony in the Imperial Palace in Tokyo several days before their wedding.
The Japanese Imperial family poses for photos at the emperor's residence in Tokyo Dec. 14, 2006. From left to right in back: Prince Akishino, Crown Princess Masako, Emperor Akihito, Empress Michiko, Crown Prince Naruhito and Princess Kiko holding Prince Hisahito in her arms. From left to right in front: Princess Mako, Princess Aiko and Princess Kako.