BERLIN – First Lady Michelle Obama and daughters Malia and Sasha visited the Holocaust memorial in Berlin, amid tight security.According to Uwe Neumaerker, director of the memorial, Michelle Obama and her daughters spent about half-an-hour Wednesday morning visiting the sea of 2711 steles that make up the memorial, which was designed by American-Jewish architect Peter Eisenman and opened to the public in May 2005, on the 60th anniversary of the end of World War II. They also were guarded by helicopters hovering over the area.Because the area had been cleared of visitors, the memorial “was totally silent and they were alone,” Neumaerker told JTA in a call after the visit. He said both Michelle Obama and her daughters had a chance to wander among the tall, tomb-like concrete slabs.“They were impressed that we Germans have such a memorial in the center of our city,” Neumaerker said, adding that he himself was impressed. Michelle Obama “really has an aura,” he said.The visitors were accompanied by Auma Obama, President Barack Obama’s half-sister, about whose existence he reportedly learned only after his father’s death in 1982. Auma Obama, 53, studied in Germany and lives in Kenya, where she was born.The visit took place as President Obama stopped in Berlin for meetings with Chancellor Angela Merkel and opposition leader Peer Steinbrück following the G-8 Summit Meeting in Ireland. Obama is to address a crowd of some 4,000 registered guests at the Brandenburg Gate later in the day, a location that is reserved for heads of state.Around that time, all windows facing the site must remain closed, including the offices of members of parliament. Even movement in front of windows reportedly is banned.The First Lady and her daughters were scheduled to spend the day immersed in the modern history of Berlin, including the Holocaust memorial visit and a stop at a memorial dedicated to the history of the Berlin Wall, which divided East and West Berlin and symbolized the Cold War between the superpowers for 28 years. The wall was rendered superfluous in 1989, and German unification soon followed.