L. E Modesitt

5,000 years in the future, humankind has spread across thousands of worlds, and more than a dozen different governments exist in an uneasy truce. But human beings have found no signs of other life anywhere approaching human intelligence. This changes when scientists discover a sunless planet they name Danann, travelling the void just beyond the edge of the Galaxy at such a high speed that it cannot be natural. Its continents and oceans have been...