Goofs

When Bran's escape pod rushes towards the Nysa, Edison counts up the acceleration rate to G-6 before telling Bran to flip the ship to decelerate. Edison then counts backwards, G-6, G-5, G-4, etc. That's not how it works in space. Once the ship got near the halfway point, it would stop accelerating and the G-force would instantly go to zero. After the ship flipped the retro rocket would have to again decelerate to a G-6 level to stop the ship at the destination. Thus, the G-forces would go up from zero to 6, not down as depicted.

Several significant plot elements are unexplained and/or unjustified, including (1) how an ice age began in what is implied to be later in the present century of global warming; (2) why the wormhole gateway orbits Earth but is much farther away from Rhea; (3) how time could be 18 times faster in Rhea-space, yet a ship built there operates normally in Earth space, and vice verse. Likewise, why doesn't the timer on the Rhean nuke run 18 times faster when it gets to Earth-space?.

While Bran was recovering from frostbite, Ohsha had plenty of time to tie up Dekker (who she knew was deeply motivated to have the ship hit the colony), yet she just left Dekker lying unconscious and unbound.