CZroe
Lifer
Myth 3: Millions Watched on Live TV
Photograph by Richard Drew, AP
In the hours and days following the disaster, footage of the Challenger accident was "replayed incessantly" on the major television networks, Neal said. This could explain why many people "remember" witnessing Challenger's destruction live on television, when in fact what they probably saw was a replay.
"It's false that most people saw the disaster live on TV," Neal said.
For one thing, most of the major TV networks did not broadcast the launch live. For another, the launch occurred on a Tuesday at 11:39 a.m., eastern time, when most people across the country were at work.
The handful of people who did see the tragedy unfold on live television were watching it on NASA's channel via satellite dishes—technology that relatively few people had at the time—or on CNN.
Published January 27, 2011
Almost everyone I know who claims to have seen it live said that they saw it in school because their schools always had the students watch live shuttle launches when they happened during class. If this was common across the country, I can see how millions could have seen it... most of them children.
Edit: I checked on the video Ichinisan linked to and the first comment was from someone who watched it in class in 7th grade. It probably was pretty common.