Challenger shuttle fragment found almost 37 years after spacecraft destroyed on lift-off

A large section of the destroyed Challenger space shuttle has been found buried in the sand at the bottom of the Atlantic Ocean off the Florida coast.

The discovery was announced by Nasa's Kennedy Space Centre in Florida on Thursday, almost 37 years after the shuttle broke apart shortly after lift-off on 28 January 1986, claiming the lives of seven astronauts including a school teacher and married mother-of-two Christa McAuliffe.

The wreckage was spotted by a TV diving crew including underwater explorer and marine biologist Mike Barnette and wreck diver Jimmy Gadomski, who were searching for the remains of a Second World War-era aircraft during filming of new History Channel series, "The Bermuda Triangle: Into Cursed Waters".

NASA has now verified the remnant was part of the ill-fated Challenger shuttle.

It measures at least 15ft by 15ft, but could be bigger because part of it is covered with sand and is thought to be from the shuttle's belly due to the presence of square thermal tiles.

The fragment is the largest ever piece of the shuttle found since the tragedy unfolded, according to Michael Ciannilli, a NASA manager in charge of the remains of Challenger and fellow lost shuttle Columbia - which broke up on re-entry over the western USA in 2003.

"Upon first hearing about it, it brings you right back to 1986," he said.

It is currently lying on the ocean bed off the coast of Florida, close to Cape Canaveral, and by law remains property of the US government.

NASA is now determining what steps to take next and has informed the families of all seven Challenger crew members about the discovery.

NASA Administrator, Bill Nelson - who was handpicked by President Biden to head the space agency - said: "While it has been nearly 37 years since seven daring and brave explorers lost their lives aboard Challenger, this tragedy will forever be seared in the collective memory of our country.

"For millions around the globe, myself included, Jan. 28, 1986, still feels like yesterday.

"This discovery gives us an opportunity to pause once again, to uplift the legacies of the seven pioneers we lost, and to reflect on how this tragedy changed us.

"At NASA, the core value of safety is - and must forever remain - our top priority, especially as our missions explore more of the cosmos than ever before."

The final challenger mission, commanded by Francis R. "Dick" Scobee and piloted by Michael J. Smith, suffered a major malfunction just 73 seconds after lift-off.

The launch, scheduled as NASA's 25th shuttle mission, saw the spacecraft waiting overnight on the launchpad at the NASA Kennedy Space Centre - when a cold front brought freezing temperatures causing ice to form.

Although some workers raised concerns, the mission was cleared for launch.

An agency investigation later showed the unexpectedly cold temperatures affected the integrity of O-ring seals in the solid rocket booster segment joints.