In the early stages of the explosion, temperatures of tens of millions of degrees were produced. The light emitted is roughly ten times the brightness of the sun. During the explosion, various types of radiations such as gamma rays and alpha and beta particles eminate from the explosion. These radiative particles give the atomic bomb its greatest deadliness. They may last years or even centuries in dangerous amounts. Gamma radiation and neutrons caused thousands of cases of radiation sickness in Japan. First the blood was affected, and then the blood making organs were impaired including the bone marrow, the spleen and the lymph nodes. When radiation was severe, the organs of the body became necrotic within a few days, marking the victim for certain death within a short period of time.