Imagine, if you will, a lone astronomer in a lonely mountaintop observatory searching the skies every night for months, years. Then one cold night he identifies a large asteroid. He tracks it. Nights become weeks. Weeks become months. He calculates. It is on a trajectory directly at earth. Total destruction of all life.
He publishes his results and warning and is ridiculed mercilessly in the press. He is hounded by the doubters and ostracized by his peers. His loneliness is now compounded by a Cassandran dread.
Until one other scientist makes independent observations and calculations that corroborate the findings. Then another. And another. And another.
As the asteroid approachs, the number of scientists agreeing rises to near unanimity. Something must be done.
However, there remain a vocal minority that refuse to accept the calculations. They continue to ridicule and demean the scientists. They pour vast fortunes of money into media spin and lobbying. They get laws passed to defund research. They scrub official documents of the words “asteroid” and “comet”.
At what point does the asteroid get close enough that the deniers become believers?