Joe Harker
On this day in 1954 the largest man-made explosion in US history occurred, and it was all because of a huge mistake with the nuclear bomb they set off.
At 6:45am local time on 1 March a nuclear bomb was tested at Bikini Atoll which was a thousand times more powerful than either of the weapons dropped on Hiroshima or Nagasaki at the end of World War Two.
Watch footage of the huge explosion here:
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Within a second of detonation there was a fireball 4.5 miles wide, which ended up being visible over 250 miles away and left behind a massive 6,500ft wide crater.
A minute after detonation the mushroom cloud was 47,000ft high and around seven miles wide, less than 10 minutes after the explosion that cloud was 62 miles wide.
This was the Castle Bravo nuclear test and it ended up being the largest man-made explosion in US history, though the people who designed the weapon hadn't intended the blast to be anywhere near as powerful as it was.
They thought the bomb they'd be detonating would be about five or six megatons, but because of a huge mistake the actual blast resulted in a 15 megaton explosion.
Around 60 percent of the lithium inside the bomb was lithium-7, which they thought would be inert but it instead contributed a whole load of extra fuel for the reaction and resulted in a far bigger blast than expected.
The results of the blast were catastrophic for the surrounding area as radioactive fallout was spread across a wide area in the Pacific Ocean, resulting in the populations of inhabited islands having to be evacuated.
When they were told they could return to their homes people found that their food sources on the islands were contaminated, and there was a rise in the rate of birth defects and thyroid tumours.
A Japanese fishing boat named Daigo Fukuryū Maru was directly hit by the fallout, resulting in many crew members suffering from radiation sickness.
Traces of fallout from the blast resulted in radioactive material being detected as far away as Europe, while the military personnel conducting the test had to shelter for hours in bunkers before it was safe to be outside again.
The Castle Bravo explosion has only been outdone by the largest and most dangerous nuclear weapons developed by the Soviet Union.
Of all the nuclear bombs tested the most devastating in the world was the Tsar Bomba, a 50 megaton bomb tested in 1961 which ended up being more than 10 times as powerful as all of the weapons used in the entire Second World War.
The Tsar Bomba's blast could be seen more than 620 miles away and was strong enough to shatter windows 480 miles away.
In theory, this terrifying bomb could have been twice as powerful, with scientists believing they could make a 100 megaton bomb but deciding to limit it to half power to reduce radioactive fallout.