How Will The Solar System End?

Stephen Battersby, New Scientist: We live in uninteresting times. Since the ructions that created the planets in the solar system’s first 100 million years — and apart from an early migration of the giant planets and the odd colliding comet not swept safely aside by Jupiter — nothing much has really been happening. The planets circle like clockwork, the sun burns steadily, and even delicate life has survived on at least one world.

It cannot last. Something unpleasant is bound to shatter this comfortable calm.

Our sun will die, of course, about six billion years from now. But things could get ugly long before that. The steady gyrations of the solar system today may conceal the seeds of chaos. Even the tiniest of irregularities can build up over time, gradually altering the paths of the planets. Between now and final sundown, it has been calculated, there is a roughly 2 per cent chance of catastrophe. Mars might drift too close to Jupiter and be thrown out of the solar system. If we’re very unlucky, hot-headed Mercury could run wild and smash into Earth.

Artist’s impression of “red giant” star ejecting matter, a potential future of our Sun.