event
damage
odds of fatality per lifetime)
preventable?
asteroid impact
Local for a small rock, global for a big one
1 in 700,000
Almost 100% preventable
Identify potential impactors, then blow them up or push them out of the way
solar flare/cme
Collapse of power grid, potential ozone depletion
0
Non-preventable, but mitigatable
Build robust power grids
supernova
Ozone depletion, radiation
1 in 10,000,000
Not preventable
gamma-ray burst
Ozone depletion, radiation, setting planet on fire
1 in 14,000,000
Not preventable
black hole
Destruction of Earth
1 in 1,000,000,000,000
Not preventable
alien attack
Humanity wiped out by aliens, space bugs give us runny noses
?
Preventable, assuming we colonize the galaxy first.
Otherwise, forget it.
death of the sun
Earth cooked to a crisp
0 †
Not preventable, but we have a long time to go yet
galactic doom
Ice ages, radiation, eaten by supermassive black hole
0 †
Not preventable, but again, none of these will happen on a human timescale
death of the universe
Decay of all matter, collapse of false vacuum
0 †
Not preventable, but dwarfs any timescale we can imagine
- Fatalities are very unlikely from a solar event, but they can still cause extensive damage.
† These events all take billions of years (at least!) to unfold, so the chances of them happening? during your lifetime are zero, but are inevitable over longer times.
Table reprinted by arrangement with Viking, a member of Penguin Group (USA) Inc., from DEATH FROM THE SKIES! © Philip Plait, Ph.D., 2008