Earth evacuation

Let's say suddenly Earth isn't going to be inhabitable for much longer,
maybe 4 or 5 years, and then it's no good. Could we evacuate Earth's
population to space, given that amount of warning? This scenario is based
upon something really bad happening that is definately going to happen(not
a maybe something will hit us). Assuming for instance that we are now in
the dark caused by a massive meteorite impact. Could we survive long enough
to get the technology together to get off the planet? Thanks,

David

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Engineers aren't boring people, we just get excited about boring things.