<P> Enola Gay stayed over the target area for two minutes and was ten miles away when the bomb detonated . Only Tibbets, Parsons, and Ferebee knew of the nature of the weapon; the others on the bomber were only told to expect a blinding flash and given black goggles . "It was hard to believe what we saw", Tibbets told reporters, while Parsons said "the whole thing was tremendous and awe - inspiring...the men aboard with me gasped' My God"'. He and Tibbets compared the shockwave to "a close burst of ack - ack fire". </P> <P> Some of the reinforced concrete buildings in Hiroshima had been very strongly constructed because of the earthquake danger in Japan, and their framework did not collapse even though they were fairly close to the blast center . Since the bomb detonated in the air, the blast was directed more downward than sideways, which was largely responsible for the survival of the Prefectural Industrial Promotional Hall, now commonly known as the Genbaku (A-bomb) dome . This building was designed and built by the Czech architect Jan Letzel, and was only 150 m (490 ft) from ground zero . The ruin was named Hiroshima Peace Memorial and was made a UNESCO World Heritage Site in 1996 over the objections of the United States and China, which expressed reservations on the grounds that other Asian nations were the ones who suffered the greatest loss of life and property, and a focus on Japan lacked historical perspective . </P> <P> The US surveys estimated that 4.7 square miles (12 km) of the city were destroyed . Japanese officials determined that 69% of Hiroshima's buildings were destroyed and another 6--7% damaged . The bombing started fires that spread rapidly through timber and paper homes . As in other Japanese cities, the firebreaks proved ineffective . </P> <Table> <Tr> <Th> Hiroshima bombing </Th> </Tr> <Tr> <Td> <Table> <Tr> <Td> </Td> </Tr> <Tr> <Td> Hiroshima in the aftermath of the bombing </Td> </Tr> </Table> <Table> <Tr> <Td> </Td> </Tr> <Tr> <Td> Strike order for the Hiroshima bombing as posted on August 5, 1945 </Td> </Tr> </Table> <Table> <Tr> <Td> </Td> </Tr> <Tr> <Td> Injured civilian casualties </Td> </Tr> </Table> <Table> <Tr> <Td> </Td> </Tr> <Tr> <Td> The Hiroshima Genbaku Dome after the bombing </Td> </Tr> </Table> <Table> <Tr> <Td> </Td> </Tr> <Tr> <Td> The greater absorption of thermal energy by dark colors resulted in the clothes pattern, in the tight - fitting areas on this survivor, being burnt into the skin . </Td> </Tr> </Table> <Table> <Tr> <Td> </Td> </Tr> <Tr> <Td> Direct, thermal flash burns . Survivor is standing as the burn is of very shallow depth; unlike burns from hot convective material, the heat transfer rate from thermal radiation is low . </Td> </Tr> </Table> <Table> <Tr> <Td> </Td> </Tr> <Tr> <Td> 22 - year old victim Toyoko Kugata being treated at the Hiroshima Red Cross Hospital (October 6, 1945) </Td> </Tr> </Table> </Td> </Tr> </Table>

Name of the second atomic bomb dropped on japan