Movies

‘Moonfall’: here’s what a successful scientific outsider REALLY looks like

Get ready to put your time in, iconoclast.

February 11, 2022

Every February, to help celebrate Darwin Day, the Science section of AIPT cranks up the critical thinking for SKEPTICISM MONTH! Skepticism is an approach to evaluating claims that emphasizes evidence and applies the tools of science. All month we’ll be highlighting skepticism in pop culture, and skepticism *OF* pop culture.

Today, we return to Moonfall, but this time astrophysicist Ryan Michney tells the story of what it looks like when a scientific outsider ACTUALLY gets something right.

Roland Emmerich’s newest disaster film Moonfall came out in theaters last week, and while I’m curious to see it, I’m also on paternity leave. My daughter’s as much explosive entertainment as I can take at the moment, so while I can’t evaluate the scientific reality of the movie, I’m not sure I’d even want to at this stage of the Emmerich oeuvre (especially not for a film that seems to involve the idea that the Moon is some kind of alien megastructure).

What I can do instead is pontificate a number of half-formed thoughts based on how the trailer looks! No longer content to merely destroy the surface of the Earth, Emmerich posits a baffling scenario in which Earth’s Moon gradually gets closer and closer to us, wreaking havoc, demolishing cities, and somehow culminating in shuttles scrawled with “Screw The Moon” flying up to fight … what seem to be robots? As custom dictates in such a film, one of the main characters appears to be a scrappy outsider whose hacking/amateur astronomy/conspiracy-theorizing skills bring them to the center of the elite governmental apparatus on a mission to confront the unfolding disaster.

John Bradley’s “Moonfall” character (probably) expounding on an imprecise array of questions, which, by sheer luck, happen to have merit in the universe of Roland Emmerich.

John Bradley (best known from his Game of Thrones role as Jon Snow’s guileless friend from the Night’s Watch, who exists to make Jon seem cooler by comparison) mugs his way through the trailer, implying that though he doesn’t work for the government, he knows more about the unfolding calamity than everyone else. This is a hacky archetype at this point, and one that’s gone some way toward convincing society that geniuses working in isolation, shunned by the establishment, are likely to be brave truth-tellers. (With vaccine hesitancy promoted by hucksters under that mantle having led to hundreds of thousands of unnecessary deaths in the past year, we can see what that notion has done for us.)

But what’s it actually like to be a scientific loner? What do you do when you think you’ve discovered something no one else accepts yet? Imagine you’re an amateur astronomer, unaffiliated with any institution, and you think you’ve discovered that the Moon’s orbit is decaying. How would you get anyone to listen to you?

The first opposition to your hypothesis will probably be that the most accurate distances to the Moon are established by bouncing laser beams off mirrors left on its surface by Apollo astronauts in the ‘70s (or the Lunar Reconnaissance Orbiter, in the same general vicinity). By timing how long the laser light takes to return to Earth, repeatedly, over several decades, we’ve pinpointed the distance with enough precision to say that the Moon is drifting away from us by 1.5 inches per year. It’s hard to imagine a loner doing a much better job than that. You’d try to tell scientists about it, they’d point at the recent data on the Moon’s distance, and that would pretty much be that.

But if you had a hypothesis that actually had merit, and you were actually knowledgeable about how to conduct research and demonstrate your findings rigorously … you still might have to wait a long time for the scientific community to recognize that you’re not a crank. There are, indeed, plenty of stories of scientists finding themselves outside the mainstream, and they’re often just as much about perseverance as they are about insight.

One such remarkable story is that of Raymond Davis Jr. and the Homestake Solar Neutrino Experiment. If the Moon falling out of the sky is the most cut-and-dry astronomical question someone could pose, the other end of that spectrum might be the question of how many superfluous neutrally-charged particles flow out of the Sun every second. Incredibly, even something that esoteric-seeming can lead to several decades of controversy.

Neutrinos are nearly massless particles emitted in the course of nuclear reactions (like those taking place constantly in the center of the Sun), which rarely interact with other matter. Every second, 100 trillion neutrinos pass through your body, but they exert no force and leave no trace. Very occasionally, one collides with the nucleus of an atom, and these rare interactions provide the only manner of observing them. Since they’re produced by nuclear processes happening deep in the Sun and stream right away without bouncing off its outer layers, neutrinos provide a direct window into the workings of a stellar furnace.

But because of their low reactivity with matter, observing neutrinos is very challenging. Modern experiments usually involve taking vast amounts of some “target” material (like water) and setting up detectors that capture a flash of light at the moment a neutrino collides with a nucleus.

In Davis’ era of the late-’60s, however, the technology to detect neutrinos that way didn’t exist. Instead, he installed a 100,000-gallon tank full of dry cleaning solution (surely, this is an oxymoron) at the bottom of the Homestake Mine (where it would be shielded from more pedestrian forms of radiation by a vertical mile of South Dakota) and waited for neutrino interactions to change a few of the chlorine atoms into argon atoms. After a month, his team would drain the tank and filter its contents to see how much argon there was.

Since you only get to see a minuscule fraction of the number of neutrinos that passed through the fluid, you have to extrapolate back to figure out how many are coming out of the Sun (like how a poll samples a few hundred people to gauge public opinion more widely). Every month, when they purged the fluid they’d find, on average, about 15 argon atoms. A tiny number to measure with precision from a volume of that size, and a tremendous feat! The only problem is that they were expecting to get 45.

Finding only a third of the neutrinos they expected was very strange. It implied that the Sun wasn’t performing enough nuclear fusion to sustain itself at its current level of brightness. There was even concern that the neutrinos were a leading indicator that the Sun had run out of fuel and was headed for a collapse.

Mostly though, other physicists simply dismissed the result. Wasn’t it possible that they estimated the number of interactions incorrectly? Or improperly dampened the likelihood of reaction somehow? Or missed argon atoms? After all, could anyone actually isolate just 15 argon atoms in an enormous amount of liquid like that? It seemed implausible.

Davis was undaunted. While his theorist partner John Bahcall repeatedly double-checked their calculations, Davis set about finding ways to demonstrate that the experiment was valid. They dispersed known amounts of radioactive argon into the tank to reassure themselves that they were actually counting it correctly. They placed other detectors at various depths of the mine to prove that they understood how much background radiation was blocked by the Earth. For years, Davis and his team performed painstaking calibrations, and kept refining the detection process. And the results kept coming back: 15 argon atoms. A third of the expected neutrinos. It wasn’t a fluke.

As the rigor of the experiment became apparent to everyone, and data accumulated year after year (from 1970-1994), the tremendous weight of scientific opinion began to shift, sluggishly, in Davis’ direction. Like a great cargo vessel attempting to turn around in a shallow canal and instead lodging itself across a busy international shipping route, it now presented a problem.

Assistance arrived, at long last, in the form of other solar neutrino experiments, which independently reached the same result. Entirely different methods of observing the particles also only saw a third of the expectation, and in 2001 physicists confirmed that neutrinos “oscillate” between three types as they travel through space. While they all start out as one “flavor” at the Sun, by the time they get to Earth, they’ve oscillated into an equal mix of all three. Since only one of those three flavors was detectable to Davis’ experiment, he only ever saw a third of the expected number.

The finding that neutrinos from the Sun were oscillating also implicitly meant that neutrinos have mass, and travel slower than the speed of light — two things that weren’t known at the time, which have significant implications for physics and cosmology. What had begun as a project to merely detect solar neutrinos had unforeseeably led to the discovery that the particle itself had an entirely new set of properties! In 2002, Davis shared the Nobel Prize in Physics, having doggedly pursued a dubious but unexplained phenomenon over the course of several decades.

Ray Davis Jr. (catwalk) looks down over the chlorine tank used in his famous experiment, circa 1967.

That is what a real case of scientific iconoclasm looks like: absorbing years or decades of skepticism about your findings as you methodically meet each challenge. Not simply enduring or dismissing criticism of your work, but joining in it — becoming your own greatest skeptic, in full awareness that you may find out you’d been wrong. Only by hardening your hypothesis on a crucible of doubt can you upturn consensus and make a major discovery.

I don’t know what Moonfall has in that regard, but I suspect Jon Snow’s friend didn’t have to be quite as careful when he discovered that the Moon was full of space robots, or invisible superstructures, or whatever was making it threaten our most destroyable manmade landmarks. Now, if only Roland Emmerich would make a movie about solar neutrinos — I would love to see that!

AIPT Science is co-presented by AIPT and the New York City Skeptics.