3 ms·

Actually, closer gamma-ray bursts would be extinction events.

• RobertoG 4y ago
  Sounds like a Fermi paradox related fact. Specially in the center of the galaxy, I suppose.
  • Archelaos 4y ago
    This is why there exists the concept of a galactic habitable zone. See: https://en.wikipedia.org/wiki/Galactic_habitable_zone https://en.wikipedia.org/wiki/Galactic_habitable_zone
    • ShamelessC 4y ago
      Some valid criticism at the end there.
• analog31 4y ago
  It would be interesting to hang a number on that, like how far away you could be and receive a dangerous dose.
• dredmorbius 4y ago
  For those curious, the lethal range is thought to be 5,000--8,000 light years, at least for supernovae GRBs, if directed toward our solar system. (GRBs are directional rather than omnidirectional.) <https://www.universetoday.com/118140/are-gamma-ray-bursts-dangerous/ https://www.universetoday.com/118140/are-gamma-ray-bursts-da...> (Via Wikipedia: <https://en.wikipedia.org/wiki/Gamma-ray_burst#Rate_of_occurrence_and_potential_effects_on_life https://en.wikipedia.org/wiki/Gamma-ray_burst#Rate_of_occurr...>) The energy released, in a few tens of milliseconds to a few hours, exceeds that of the Sun over its entire 10+ billion year lifespan. (I'm not sure if neutron star / black hole events might trigger larger emissions lethal at greater ranges.)
• pencilguin 4y ago
  I wonder about a merger of a pair of supermassive black holes, say a billion solar masses each. Would it sterilize the whole galaxy? A galaxy is a pretty dangerous place to be. Probably we should get clear at first opportunity. A pretty big pair is scheduled to merge sometime in the next three years. Probably we will get enough warning to be watching carefully when it happens.