Ancient supernovae found written into the Antarctic ice

 作者:闻人鹗     |      日期:2019-03-09 07:16:01
THE signature of ancient supernova explosions may be written into the ice of Antarctica. The gamma radiation from supernovae is thought to produce nitrogen oxides in the atmosphere, which are then converted to nitrates. As the nitrates could be trapped in snowfall, it is possible that glaciers hold evidence of past supernovae. Yuko Motizuki of the RIKEN research institute in Wako, Japan,