The science and controversy behind Netflix’s ‘3 Body Problem’

globalnews.ca:

Netflix’s 3 Body Problem has sparked fascination and controversy.Based on the 2008 novel by Liu Cixin and brought to the small screen by Game of Thrones creators D.B. Weiss and David Benioff, the series tells the story of an impending alien invasion of Earth.The show portrays some science that left some viewers with questions and some historical events that have upset some people in China.Global News spoke to experts to separate fact from fiction and history from hysteria.A three-body problem refers to three astronomical bodies, like planets or suns, and how each object’s gravity impacts the other’s orbits.But it’s easiest to understand if we start with a two-body problem.“The closer objects are, the stronger is the gravitational pull,” York University professor emeritus of physics and astronomy Paul Delaney said.The sun is about a million times larger than the Earth, according to NASA, and so its gravity holds our planet in orbit around it.The orbit is stable, making it predictable, Delaney said.This is a two-body problem, just like the moon and the Earth, and it’s a problem that’s been solved since Sir Isaac Newton’s work on gravity.“We can theoretically figure out where (the two objects) will be as a function of time,” Delaney told Global News.“There are complications with angular momentum and tidal forces and friction,” he said, speaking from Tuscon, Ariz., “but to all practical intents and purposes, the moon will stay in a stable orbit.”There are other planets in the solar system and the moon orbits Earth.