When Worlds Collide — Philip Wylie

A runaway planet hurtles toward the earth. As it draws near, massive tidal waves, earthquakes, and volcanic eruptions wrack our planet, devastating continents, drowning cities, and wiping out millions. In central North America, a team of scientists race to build a spacecraft powerful enough to escape the doomed earth. Their greatest threat, they soon discover, comes not from the skies but from other humans.