On: Scientists track down the source of mysterious radio bursts

[cjfont]

According to the article, supernovas occur more frequently in younger galaxies, and we know these can blow a star's heliosphere away temporarily exposing all its planets to deadly radiation (which it seems has happened to Earth before).

[schwarrrtz → cjfont]

Also, stars that are large enough to experience a supernova have shorter lifespans than our Sun, giving less time for life to develop.