But they, the Challenger Seven, were aware of the dangers, overcame them and did their jobs brilliantly.

CNN: On the space shuttle explosion

President Reagan had planned to deliver his annual State of the Union address on the day the space shuttle Challenger exploded killing all seven crew members aboard.

CNN: On the space shuttle explosion

Cameron became the first man to complete a solo dive to the Challenger Deep, which is seven miles beneath the surface of the Pacific Ocean.

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Apollo's successor, the Space Shuttle program, failed to capture America's imagination, or attention, except in 1986, when Challenger blew up, killing seven, and in 2003, when Columbia disintegrated on reentry, killing another seven.

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In 1986, seven astronauts died after the Challenger space shuttle exploded 72 seconds after lift-off from Cape Canaveral.

CNN: Wednesday,

Endeavour was built to replace the Challenger ship which was lost, along with her crew of seven, in a catastrophic accident in 1986.

BBC: Shuttle Endeavour launches one last time

Challenger blew up after launch January 28, 1986, killing all seven crew members, including school teacher Christa McAuliffe.

CNN: R O C K E T M A N

The billionaires are bankrolling expeditions to reach the deepest place in the ocean, a spot called the Challenger Deep that lies at the bottom of the Mariana Trench, seven miles below the surface of the South Pacific.

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One example that See uses in the classroom: the 1986 Challenger disaster, when the space shuttle blew apart 73 seconds into its flight, killing the seven crew members.

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