Even when we do manage to stay focused, people of all ages inadvertently change, edit, and manipulate the details. Science tells us that many of our episodic memories — the ones that tell the stories of our life’s most emotional moments — turn out to be dead wrong.

In a landmark study conducted the day after the tragic Challenger space shuttle explosion in 1986, researchers asked a group of 44 college students about their knowledge of the event. Nearly all expressed confidence about where they were and what they were doing at the time they heard the news.