It was 28 years ago today, Jan. 28, when the Space Shuttle Challenger exploded in the sky just over a minute after launching from Cape Canaveral, Fla.

The tragic explosion resulted in the deaths of seven crew members -- Commander Francis R. Scobee; pilot Michael J. Smith; mission specialists Judith A. Resnik, Ellison S. Onizuka and Ronald E. McNair; and payload specialists Gregory B. Jarvis and Sharon Christa McAuliffe.

McAuliffe would have been the first teacher in space.

According to NASA, the explosion happened 73 seconds after liftoff. Click here to read NASA's explanation of the cause of the explosion on that day, and what the crew would have done had the tragedy not occurred.