Obama and his wife, Michelle, boarded Air Force One under cold, rainy skies Monday morning for the long flight. The occasion presented an opportunity for a rare get-together of American presidents. Former President George W. Bush was already on board the plane, along with former first ladies Laura Bush and Hillary Clinton.
Former President Bill Clinton was traveling separately from Rio de Janeiro, where he was attending a Clinton Global Initiative event. And former President Jimmy Carter also planned to join the group in Johannesburg.
George H.W. Bush is the only living president who will not attend. His spokesman said the 89-year-old no longer is able to travel long distances.
The American leaders will join dozens of other dignitaries and tens of thousands of mourners at the memorial service at a Johannesburg stadium. Mandela will be buried Dec. 15, following a state funeral in his hometown of Qunu.
Obama has called Mandela a personal hero, and his own political rise has drawn inevitable comparisons to the former South African leader. Each was his nation’s first black president and a winner of the Nobel Peace Prize — though those close to the U.S. leader say he is aware of the vast differences in the politicians’ experiences.