An asteroid is going to strike the Earth, sending up a cloud of smoke and ash and
pulverized rock that will swathe the Earth in gloom, causing winter to last a hundred
years
And an ice age is coming, and everything humans have built will be ground to sand
underneath miles-thick sheets of ice
As we kill ourselves with nuclear war
And the global ecosystem will collapse
A nearby star will go supernova and the radiation from the explosion will turn our
atmosphere into nitric acid
While supervolcanoes below Yellowstone erupt with the force of a thousand Krakatoas
We're running out of resources
And civilization will collapse, and savages will squabble futilely over the ruins that are
left
As we're turning the atmosphere slowly to carbon dioxide, leading to greenhouse effect
that will lead to the oceans boiling dry
And the population is growing without bounds, leading us to inevitable mass starvation
While antibiotic resistant superdiseases are evolving to kill us all
Except that our own bioengineered plagues will kill us faster
And nanotechnology running amok will turn us into gray goo
But our radio transmissions to outer space will someday be detected, and highly evolved
civilizations will come and find us - They will be predatory, for any civilization honed by
a billion years of evolution must be a fierce competitor. It's only a matter of time.
Our machines will outstrip us. Someday they'll decide we are redundant, wasteful.
We'll move ourselves to cyberspace, but we'll all die when nobody's left to keep the
infrastructure running.

Our galaxy is going to collide with the great nebula of Andromeda,
but before that, the sun will have turned into a red giant, and swallowed the Earth.
A trillion years after that, the last star will burn out.
None of us will see it.
Here's the truth nobody wants to acknowledge: we're going to die.
For each of us, one of these dooms will come true.