Mike Wong (PhD ’18) Explains the Real Science of the “3 Body Problem”

by Andrew Moseman

Caltech alum Mike Wong (PhD ’18) is a major Star Trek fan. He uses his podcast, Strange New Worlds, to explain the real science behind the show’s science fiction. But Star Trek isn’t the only television show to grab his attention.

As a guest on a new episode of the NPR podcast Short Wave, Wong, now an astrobiologist and planetary scientist at Carnegie Science, dives into the science of 3 Body Problem, the sci-fi bestseller turned Netflix series. [NOTE: Plot spoilers below.]

First there is the astrophysics conundrum that lends its name to the show. As Wong explained on the podcast, in astrophysics, the three-body problem refers to the devilishly difficult task of resolving “how you predict the motions of three mutually gravitating astronomical objects.” With just two bodies, the math is relatively straightforward, Wong says. But when you introduce a third, it becomes a chaotic system whose movements are difficult to predict with precision.

In 3 Body Problem, extraterrestrials called the San-Ti come from a planet that orbits one star in a three-star system—but, occasionally, their world swings into erratic orbits that cause catastrophic climate variations. It might enter an orbit around one of the other two stars or swing far away from all three stars, making it frigid, or gets caught between two stars and becomes suddenly scorching. The aliens venture to Earth because of its calm and predictable environment … and chaos ensues.

The show’s science is correct in many ways, Wong told the podcast hosts. Specifically, the aliens come from Alpha Centauri, a triple-star system that is just a few light years from Earth in reality. But it takes the San-Ti centuries to arrive because the show does not grant them the ability to travel at anything close to light speed. Wong added that it is true that the closest of Alpha Centauri’s three stars, Proxima Centauri, does indeed possess a planet in the “Goldilocks zone”—the area that is not too far nor too close to the star—that could be habitable because it is the right climate for liquid water to be present. “It’s just really amazing to think that, yeah, there’s actually a habitable world that may have an alien civilization on it for all we know just four light years away,” he said.

Wong added that not everything in the show is science fact. For instance, that potentially habitable world, called Proxima Centauri b, is not in a chaotic orbit, as stated in the show. It does not leave its host star and swing around the other two.

So, if aliens from there are headed here, it would not be for the reasons depicted on 3 Body Problem.