Aram Boghosian for The Boston Globe

Katie Pakenham (left) and Teresa Mathai consoled each other as family and friends of those lost on Sept. 11, 2001 gathered in Boston.

Aram Boghosian for The Boston Globe

Faye Kane, who lost her 26-year-old daughter, Jennifer Kane, in the attacks, flowers at the memorial at the Boston Public Garden.

Aram Boghosian for The Boston Globe

Senator Scott Brown (left), and his wife Gail Huff, attended the Boston ceremony.

Aram Boghosian for The Boston Globe

Boston Police officers and bystanders along Beacon Street listened to the National Anthem at a a State House ceremony.

Gary Hershorn/REUTERS

A man placed a US flag next to a memorial bearing two pieces of steel from the World Trade Center in Weehawken, N.J.

Chang W. Lee/Getty Images

Anna Favuzza made a rubbing of the name of her brother, Bernard D. Favuzza, who was a victim of the World Trade Center attacks.

Jason Reed/REUTERS

President Barack Obama and first lady Michelle Obama observed a moment of silence on the South Lawn of the White House.

Justin Lane/REUTERS

New York City police bugler Gabe Perdomo played next to the 9/11 memorial.

Timothy A. Clary/Getty Images

Dennis Swindell kissed the name of his partner, Gary Lee Bright, inscribed on the South Tower memorial pool wall.

Eric Thayer/REUTERS

Maria Rodriguez wiped her eyes near pictures of a victim before ceremonies marking the 11th anniversary of the attacks in New York.

Shannon Stapleton/Reuters

A man stood along Trinity Place in New York City before ceremonies began to mark the 9/11 anniversary.

Gary Hershorn/REUTERS

One World Trade Center, the tower being built in a new World Trade Center complex, is seen at right from New Jersey.

Adrees Latif/REUTERS

The Tribute in Light illuminated the sky over New York's lower Manhattan skyline on Sept. 10.

NASA

A NASA satellite captured a plume of smoke rising from the World Trade Center in New York City on Sept. 11, 2001.