In the end, there won't even be fragments.
If nature is left to its own devices, about 7.59 billion years from now Earth will be dragged from its orbit by an engorged red Sun and spiral to a rapid vaporous death. That is the forecast according to new calculations by a pair of astronomers, Klaus-Peter Schroeder of the University of Guanajuato in Mexico and Robert Connon Smith of the University of Sussex in England.
Their report, to be published in the Monthly Notices of the Royal Astronomical Society, is the latest and gloomiest installment yet in a long-running debate about the ultimate fate of our planet. Only last year, the discovery of a giant planet orbiting the faint burned-out cinder of a star in Pegasus had suggested that Earth could survive the Sun's death.
Dr. Smith called the new result "a touch depressing" in a series of e-mail messages. But "looked at another way," he added, "it is an incentive to do something about finding ways to leave our planet and colonize other areas in the galaxy."