A quarter-century later, images of the exploding space shuttle Challenger still signify all that can go wrong with technology and the sharpest minds. The accident on Jan. 28, 1986 - a scant 73 seconds into flight, 14 kilometres above the Atlantic for all to see - remains NASA's most visible failure.
This 1986 file photo provided by NASA shows the crew of the space shuttle Challenger, from left, Ellison Onizuka, Mike Smith, Christa McAuliffe, Dick Scobee, Greg Jarvis, Ron McNair and Judith Resnik.
In this 1986 file photo, Christa McAuliffe, left, and Barbara Morgan, right, laugh during training.
In this Jan. 27, 1986 file picture, the crew members of space shuttle Challenger flight 51-L, leave their quarters for the launch pad at Kennedy Space Center in Cape Canaveral, Fla. From foreground are commander Francis Scobee, Mission Spl. Judith Resnik, Mission Spl. Ronald McNair, Payload Spl. Gregory Jarvis, Mission Spl. Ellison Onizuka, teacher Christa McAuliffe and pilot Michael Smith.
(Steve Helber/Steve Helber/The Associated Press)
In this Jan. 28, 1986 picture, the space shuttle Challenger lifts off from the Kennedy Space Center in Cape Canaveral, Fla. shortly before it exploded with a crew of seven aboard.
(Thom Baur/Associated Press)
In this Jan. 28, 1986 file photo, the space shuttle Challenger explodes shortly after lifting off from Kennedy Space Center.
(BRUCE WEAVER/BRUCE WEAVER/Associated Press)
In this Jan. 28, 1986 file picture, two unidentified spectators at the Kennedy Space Center in Cape Canaveral, Fla. react after they witnessed the explosion of the space shuttle Challenger.
This Jan. 28, 1986 file picture shows U.S. President Ronald Reagan in the Oval Office of the White House after a televised address to the nation about the space shuttle Challenger explosion.
(Dennis Cook/Dennis Cook/Associated Press)
NASA Administrator Charles Bolden lays a wreath as other NASA personnel watch during ceremony as part of NASA's Day of Remembrance at Arlington National Cemetery Jan. 27, 2011 in Arlington, Va.
(Bill Ingalls/NASA/Bill Ingalls/NASA)
A wreath stands at the memorial for the Challenger Space Shuttle at Arlington National Cemetery in Arlington, Va., on Jan. 27, 2011, to commemorate the agency's National Day of Remembrance.
(SAUL LOEB/SAUL LOEB/AFP/Getty Images)
A wreath commemorating the seven astronauts who perished in the space shuttle Challenger accident rests in the Astronaut Memorial Tree Grove during the annual National Day of Remembrance ceremony at the Johnson Space Center on Jan. 27, 2011, in Houston.
(Smiley N. Pool/Smiley N. Pool/Houston Chronicle/Associated Press)