Target Earth -- Sunburn -- The stellar fury of supernovae -- Cosmic blowtorches -- The bottomless pits of black holes -- Alien attack! -- The death of the sun -- Bright lights, big galaxy -- The end of everything.
Summary
It's only a matter of time before a cosmic disaster spells the end of the Earth. But how concerned should we about about any of these catastrophic scenarios? And if they do post a danger, can anything be done to stop them?
