Television researcher Nielsen and Sony Electronics partnered to find which TV events were the most memorable for audiences. The Challenger space shuttle disaster in 1986 and death of Osama bin Laden rounded out the top five.

"What we were trying to measure was perception," Paul Lindstrom, a senior vice president at Nielsen told Reuters. "The most significant things, when it comes to television, weren't the events, but the moments shared with people. Things like ‘watching baseball with my dad,' seeing the Olympics together, all those types of things brought emotional memories together."

The study questioned 12,000 participants online over three days in February, resulting in 1,077 completed surveys from which results were compiled. Respondents were provided a list of choices selected by media experts that ranged from news coverage such as the assassination of President John F. Kennedy in 1963 to pop culture events such as the airing of final episodes of "Friends," "Seinfeld," and "Cheers."

News-oriented items that crossed generations proved to be the most influential TV experiences, and stories of a communal nature or with widespread relevance also resonated with viewers.

Princess Diana's funeral, the Columbine High School shootings in Colorado, the BP oil spill in the Gulf of Mexico, the 2010 earthquake in Japan and football star O.J. Simpson's famous car chase by police also scored in the top 10.

"What's interesting for me is not what's on the list, but what's not on the list," said Brian Siegel, vice president of television for Sony Electronics. "There wasn't entertainment - no Super Bowl, no "Friends" finale. It was all news and events ... Memories that are ubiquitous among all of us."

Sony commissioned the study to assess emotions that audiences attach to TV with an eye toward boosting its program development and marketing.

Following is a list of the top 20 most impactful TV moments of the past 50 years, according to the study.

1 September 11 attacks 2001

2 Hurricane Katrina - the levees break 2005

3 OJ Simpson murder verdict 1995

4 Challenger space shuttle disaster 1986

5 Death of Osama bin Laden 2011

6 OJ Simpson high-speed car chase 1994

7 Earthquake/tsunami in Japan 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 acceptance speech 2008

14 Prince William, Kate Middleton wedding 2011

15 Assassination of John F. Kennedy 1963

16 Oklahoma City bombing 1995

17 Bush/Gore election results 2000

18 Los Angeles riots/Rodney King beating 1992

19 Casey Anthony murder trial verdict 2011

20 Funeral of John F. Kennedy 1963

(Reporting by Courtney Garcia; Editing by Bob Tourtellotte and Lisa Shumaker)

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