What are TV’s 20 most memorable moments?

What TV memories brought the country together, and which ones are emblazoned on Americans’ brains? Almost 11 years after the terrorist attacks on the World Trade Center and the Pentagon, 9/11 remains a vivid and unforgettable memory for viewers across the country, topping the list of CBS’ Top 20 Memorable Television Moments.

A study by Sony Electronics and Nielsen ranked TV moments based on their impact — viewers’ recollection of the TV moment, their memory of where they were when they watched it and if they talked to others about it.

Taking the No. 1 spot is the TV coverage of the Sept. 11, 2001, terrorist attacks, which resulted in the deaths of nearly 3,000 people, including 227 airline civilians and 19 hijackers.

2005’s devastating Hurricane Katrina filled No. 2. Killing more than 1,836 people, Katrina was named one of the five deadliest hurricanes in the history of the U.S. as well as the costliest natural disaster, with total property damage estimated at $81 billion.

The third TV moment drew such a large audience that people nationwide stopped working, causing an estimated $480 million in lost productivity. On Oct. 3, 1995,O.J. Simpsonreceived a “not guilty” verdict, acquitting him of the killings of his ex-wife Nicole Brown Simpson and her friend Ronald Goldman.

The Space Shuttle disaster of 1986 — No. 4 — took place on Jan. 28, 1986, when the Challenger broke apart 73 seconds into its flight, resulting in the deaths of its seven crew members. The spacecraft disintegration ensued after an O-ring seal in its right solid rocket booster failed at liftoff.

Rounding out the top five is the killing of former al-Qaeda leader Osama bin Laden in Pakistan on May 2, 2011, by Navy SEALs. Ordered by President Obama and led by the CIA, Operation Neptune Spear’s raid on bin Laden’s compound in Abbottabad, Pakistan, ended in Bin Laden’s death.

The rest of CBS’ Top 20 Memorable TV Moments are a mix of national tragedies, political high and low points, natural disasters and celebrity spectacles:

6)O.J. Simpsonhigh-speed car chase, 1994

7) Japan’s earthquake/tsunami, 2011

8) Columbine school shooting, 1999

9) BP oil spill in the Gulf of Mexico, 2010

10) Funeral of Princess Diana, 1997

11) Death of Whitney Houston, 2012

12) Capture and execution of Saddam Hussein, 2006

13) Barack Obama presidential acceptance speech, 2008

14) Prince William, Kate Middleton wedding, 2011

15) Assassination of President John F. Kennedy, 1963

16) Oklahoma City bombing, 1995

17) Bush-Gore election results, 2000

18) Rodney King beating/Los Angeles riots, 1991-92

19) Casey Anthony murder trial verdict, 2011

20) Funeral of President John F. Kennedy, 1963

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