Scientists have crunched the numbers. Life on this planet will cease to exist in as little as 1.75 billion years. Or as much as 3.25 billion years. Andrew Rushby of the University of East Anglia in Britain came up with two different models that estimate how long Earth will remain in a "habitable zone" around the sun. Too close and the planet becomes super-heated and all water disappears. Too far and it becomes an icy wasteland. As our sun gets older it will evolve into a larger more luminous star. When that happens, sometime between 1.75 billion and 3.25 billion years from now, the 92.9 million miles between us and the sun will not be enough. It will be game over. It's hard to imagine, but it most definitely will happen.

Now we can always kill off our own species through our own stupidity with biological warfare run amok, or kill off everything with an all out nuclear holocaust. Barring that, we now have a rough countdown clock. It's hard to imagine what those final days would be like. They say humans won't be here to see the very last day of life on the planet though. We would check out far sooner than other forms of life. Scientists say in the end, the last thing to remain until the final day will be microbes. Those, and the bonds still not paid off from the Turnpike Authority.