"Flip right now and burn like hell and I can get us within 50,000 clicks," ship's navigator Ade Nygaard announces in the first episode of SyFy's fascinating space opera "The Expanse". The rest of the freighter Canterbury's crew looks appalled. A working stiff rolls her eyes.
"Oh great, then we'll all be puking in our crash couches while the cargo busts loose and scuttles the ship."
This snippet of dialogue sets up one of the most inventive scenes ever seen on screen in science fiction. Past movies and shows from "Star Trek" to "2001: A Space Odyssey" sidestepped the fundamental problems of space travel with imaginary physics or by skipping them entirely. "The Expanse", which aspires to be a sort of interplanetary "Game of Thrones", relishes them.
"The Expanse" lacks George R.R. Martin's endlessly compelling characters, but its world rivals the meticulous beauty of Westeros. In this future, humans have settled the solar system but gone no further. Outposts proliferate throughout the asteroid belt and civilization thrives on Mars. The people of Earth live in luxury. Like the British Empire at the height of its power, the United Nations saps its starving colonies of resources and spreads the wealth at home. Militarized, autonomous Martians challenge Earth's dominion in a simmering cold war. Meanwhile, "Belters", a sort of space-proletariat, live meager lives with little oxygen or water and illness from childhoods in low gravity. But, with all the furor of pre-war Bundists, a workers' revolution foments.
That far-flung society depends on a massive, high-speed stellar freight system, of which the Canterbury is part. The ship and its crew are on their way to the dwarf planet Ceres with a huge cargo of ice when they hear a distress call. This prompts the choice to "flip and burn" — to turn the ship and blast their engines against the massive inertia hurtling them along their original course.
In most science fiction, this maneuver would be no big deal. How many times have we watched the Millennium Falcon barrel roll in four movies?
Not so in "The Expanse". In this universe everyone traveling through space has to deal with the overwhelming physical pressures that modern astronauts and fighter pilots experience in extreme situations like launch and landing. In fact, to account for the higher speeds of interplanetary travel and lower concern for human-well being, the pressures are even greater. Thus the working stiff's unwillingness to change course. She's less worried about being late to Ceres than her bones shaking apart mid-turn (not to mention the ship around her). Unless we make massive strides in gravity technology in the next few centuries (a premise on which nearly all other science fiction rests) this is the reality future spacefarers will have to deal with.
Pilots have a few tricks for dealing with this. G-suits squeeze their legs like vises, forcing blood up from their legs into their organs and brains. Flexing certain stomach muscles can help as well. But the most important pieces of that puzzle are strong hearts and avoiding sustained high-g maneuvers altogether.