India, Nov. 4 -- Two words written in the flight log of the American bomber that dropped the atomic bomb on Hiroshima have helped scientists uncover new evidence about how high smoke from the devastating explosion rose into the atmosphere 81 years ago.

As per a report by ScienceAlert, the entry, "CLOUD GONE", was written by navigator Theodore Van Kirk on August 6, 1945, just 97 minutes after the bombing. Researchers now believe the observation provides rare evidence that the resulting firestorm sent soot at least 11.3 kilometres into the sky.

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The American B-29 bomber Enola Gay dropped the atomic bomb, codenamed Little Boy, on Hiroshima at 8.15 am local time. As ...