Project Reverb

Two thousand nine hundred kilometers beneath the Pacific, Earth's outer core has begun to freeze — and when it stops churning, the magnetic field dies and the sky goes with it. Physicist Noor Kharazmi has fourteen months, a commission that would rather bury four hundred thousand survivors than gamble on saving nine billion, and one wild idea: a nuclear-driven pulse fired down a bore into the deep Earth. Everything depends on whether she is right.