Remembering Challenger: 35 years since tragic explosion

Thursday marks 35 years since the space shuttle Challenger disaster. It is also NASA's annual day of remembrance to honor the astronauts who have lost their lives during missions.

CAPE CANAVERAL, Fla. - Thursday marks 35 years since the space shuttle Challenger disaster. It is also NASA's annual day of remembrance to honor the astronauts who have lost their lives during missions.

Hundreds of people in Florida and millions watching on live television witnessed the space shuttle Challenger break apart in a mid-air explosion on January 28, 1986, killing 7 people on board.

The blast occurred 73 seconds after takeoff from the Kennedy Space Center in Cape Canaveral, Fla. The Challenger's fuel tank collapsed, resulting in an explosion that killed the seven people on board and sent debris flying into the Atlantic Ocean.

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The explosion marks one of the darkest days in the space program's history.

One of the crew was Sharon Christa McAuliffe, a 37-year-old high school teacher from New Hampshire and the first civilian ever chosen to go to space.

(NASA)

McAuliffe says: "I don't think any teacher has ever been more ready to have two lessons in my life. I've been preparing these since September and I just hope everybody tunes in on day four now to watch the teacher teaching from space."

Many children gathered in their classrooms to watch the historic event, only to see the shuttle go up in flames.

(NASA)

On the ground at Cape Canaveral, hundreds witnessed the doomed launch in-person, including McAuliffe's parents. After the explosion, then-President Ronald Reagan postponed his State of the Union address, and instead delivered a televised eulogy to the American people.

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Reagan said: "The Challenger 7 were aware of the dangers but overcame them and did their jobs brilliantly."

35 years since space shuttle Challenger explosion

Thursday marks 35 years since the space shuttle Challenger disaster. It is also NASA's annual day of remembrance to honor the astronauts who have lost their lives during missions.

An investigation later found NASA was aware that the freezing temperatures could cause problems for the rocket boosters, but decided to go ahead with the launch anyway.

In March, the U.S. Mint will release a commemorative coin in honor of teacher Christa McAuliffe.

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