The Visitors

At the turn of the twenty-third century, humanity has colonized much of our solar system. The emerging Sol System culture, largely independent of Earth, is based on asteroid mining and low-gravity processing and manufacturing. The capital city of Mars, Hawkington, is the hub of government, industry, science and technology, education, and the arts. Humanity has faced and overcome the challenges of colonizing space and the resurrection of a nearly-destroyed home world.
But is it prepared for the next challenge? 309 pages.