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what if I told you that supernovas
aren't the brightest events in the
universe gamma-ray bursts are they shine
hundreds of times brighter and only last
for several minutes at most but even a
second would be enough for them to mess
up all complex life on the planet this
is what if and here's what would happen
if a gamma-ray burst hit the earth
gamma-ray bursts or gr bees are the most
violent explosions in the universe they
occur when two neutron stars collide and
form a black hole or when a black hole
swallows a neutron star or when a star
goes supernova they're outside the
spectrum of visible light that's why you
can't see them with your naked eye but
you'd feel their effect if they were to
hit the planet
one of those bursts might have already
triggered a mass extinction here on
earth but that mighty event was 450
million years ago long before even the
first dinosaurs started roaming the
planet if a gamma-ray burst hit us today
we might have a chance to make it out
alive maybe a blast from 3,000 light
years away from us wouldn't be too bad
even though the earth would absorb most
of the radiation the blast emitted the
only things that would be in danger down
here would be our satellites some of
them would get knocked offline
permanently you might lose your internet
connection but it wouldn't take long
until most of the malfunctioning
satellites were restored
if the gamma ray burst blasted from only
500 light-years away it would change the
game completely the radiation that would
rain down on earth would destroy our
ozone layer almost all of our plant
species would die there wouldn't be
enough of them left to sustain
photosynthesis and with that the amount
of oxygen in our atmosphere plant eating
animals would starve and the rest of
them would be left to suffocate humans
could try to save ourselves with oxygen
masks but even that wouldn't help us
last too long if a gamma-ray blasted
anywhere closer the damage from it would
be equivalent to the earth getting hit
by an asteroid first it would
immediately destroy our atmosphere
without the atmosphere
we'd be bathing in UV rays getting
severe sunburns and trying to figure out
how to restore the planet's atmosphere
before this hostile environment killed
us completely there is good news gamma
rays have such a short wavelength that
with a bit of luck the beam could pass
relatively close and do no significant
damage but have we ever been so lucky
nothing absolutely nothing would be as
devastating as the direct hit of a
gamma-ray burst from within our galaxy
the Milky Way if it makes you feel any
better our satellites would detect the
GRP immediately but what could we do
once we found ourselves in the
crosshairs of this all-natural galactic
phaser as the burst was approaching the
planet photons would be pulling the
ozone layer away and causing chemical
reactions on earth you'd see a cloud of
photochemical smog covering the planet
we'd be blasted with all sorts of cosmic
rays they would damage our electronics
and bring us lethal doses of radiation
you'd witness another wave of mass
extinction on earth the good thing is
that it doesn't look like an event like
this is likely to happen for another
billion years by that time we might have
figured out how to move the earth out of
the danger zone
but that's a story for another what-if
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