Dangers to life on Earth from space:
Cosmic rays, gamma rays, and a Coronal Mass Ejection (CME) from sun,
Wandering star or black hole (used to be a star),
Aliens wanting something (water, uranium, slaves, invite you to a barbecue),
Human launched missiles with atomic warheads.
Only that last one and maybe the first one or two or three have any real chance of doing you in during your short (comparitively) life span.
Many of the science tv shows, politicians, and the Internet that try to make us afraid of most anything.