The Sins of the Fathers
This book can be downloaded and read in iBooks on your Mac or iOS device.
A scientific expedition travels into deep space, and brings back shocking news: the galactic core has exploded -- and the Earth is doomed! Suddenly, a small group of men -- and one very wise young woman -- find that the fate of the planet is in their hands. When an alien race arrives, offering a slender ray of hope, it is impossible to know whether they can be trusted. But perhaps the greatest challenge of all will be to get people to respond to a danger that cannot be seen, that is distant in time and space, and will kill everyone if the decision is too late in coming.
Includes a new introduction by Ben Bova, editor of the original Analog serials, plus the essay 'How to Move the Earth' by the author.