Behind the Moon, Inside Apollo: Profile of a Rocket Scientist

Neil Armstrong’s boot dented the surface of the Moon at 10:56 p.m. on July 20th, 1969. It was a feat repeated eleven times over the next three years, then never again, something that today’s astronauts will almost certainly never get the chance to do.

The Moon landings are the greatest technological accomplishment in human history. They might also be our greatest team effort. Armstrong and Aldrin walked our only natural satellite based on billions of hours of work from hundreds of thousands of the world’s brightest minds. Their footprints were the pinnacle of a collective achievement.

A chemical engineer named Roberta Villavecchia helped put them there. This is her story.

The billion hour footprint

Roberta and Apollo

Roberta, or Robyn, grew up in California. She put herself through what would become New Mexico State University as a cooperative student. That meant each year of college was split in two, spending six months on full-time studies while working part-time at the White Sands Missile Range, then switching to part-time studies and full-time rocketry.

She says that her work at White Sands gave her the first itch for space: “I didn’t get very close to rockets at the time, but it was a connection. And it was exciting.”

Robyn graduated, majoring in chemistry. After a dull spell working in a foodstuff purity lab in California where her primary duty was to check for bits of insects, she came back to White Sands. She got a job with Aerojet General, working at the Missile Test Facility on the opposite side of the mountain to the Missile Range. Kennedy’s mandate was just coming into being here, and work was starting on the engines of the Lunar Module; an elevator craft which would take the astronauts from the orbit around the Moon to a gentle landing on its surface. Robyn began work in the chemistry lab, testing propellants.

Robyn wears large, sparkly glasses and has a short wave of hair which sits back off her face. All her movements are energetic and there’s no hint of laziness about her. Speaking to her is invigorating.

Things were only just getting started. Robyn was soon chosen to leave Arizona and set up at her penultimate spot in Florida, just 15 miles from the Vehicle Assembly Building (VAB). She was given a disused chicken ranch as a temporary base, where snakes and alligators roamed the parking lot. From there, she and her team began to plan out a cutting edge laboratory to test the fuels which would push humans, metal and plastic to the Moon and back.

Robyn recalls what her boss, Dan Kinds, told her when she arrived at her slice of swamp: “Your office is over there. It’s the back bedroom. You’ll find a bunch of catalogues in there. We gotta spend 26 million dollars in the next month and a half or we’ll lose the appropriation, so start buying stuff.”

She did buy stuff, all the essentials for kitting out a state of the art laboratory. She also got some chemists: “I hired some friends from White Sands and a couple of guys from Patrick Air Force base and got in a lot of trouble with NASA for poaching. We built the wet-lab.”

The project grew, finally arriving, with Robyn and her team of chemists in tow, to nestle itself under a huge bulb of liquid nitrogen, sandwiched between the VAB and the launch pads. Robyn had reached The Crawlerway.

Density, Purity, Viscosity

The new lab was right in the beating heart of Cape Canaveral, within rumbling distance of the Crawlerway.

Robyn's lab sat nestled under the white bulb of liquid nitrogen seen above and to the left of the Saturn V

Robyn’s team was tasked with determining the density, viscosity and purity (DVP) of the propellants which would be used in the lunar lander to ease humans gently onto the surface of the Moon. This was far more than mundane chemistry, for two reasons.

Firstly, Robyn’s team had to determine the DVP of the propellants to unheard of degrees of accuracy. At the time, the most accurate measures of these properties went to five decimal places. Robyn’s team was asked to go to nine places, 10,000 times more precise – the difference between measuring the length of a car and the width of a hair using a meter stick.

On top of that, the propellants in question were not your average school lab chemicals. As Robyn puts it:

To complicate things, the propellants to be used were hypergollic. Now they are nasty items. They kill you in a New York minute. Firstly they’re extremely toxic. Take nitrogen tetroxide [an extremely weak compound which makes up one half of Aerozine as used in the Lunar Module engines]. Get a whiff of that and it mixes with water and forms nitric acid inside your lungs. Next thing you know you’re dissolving from the inside out. It’s not a pretty picture. We were trying to play with this stuff in a way that wouldn’t kill us, as well as trying to determine physical properties that have never been determined before. And there were five of us.

One aerospace engineer from the current generation of rocket scientists, Evie Marrom, said of hypergolic fuels: “They have a bad tendency to ignite spontaneously and are horribly volatile. You know they’re bad when seasoned guys turn around and walk away at the mere mention of using them.”

The reason that the density, viscosity and purity were so important was that those quantities governed the burn rate of the LM engines on descent to the Moon. If Robyn’s team miscalculated the density, that meant a tank of fuel would weigh less, burn out sooner and potentially, even for a tiny error, leave the LM in free fall above the surface of the Moon.

Robyn put it like this: “Do you know how thin the skin on the lander was? You could put your finger through it. If you ran out of fuel ten feet off the lunar regolith, you were dead. We had to know in our own souls that we were right.”

About Hal Hodson

Hal is an astrophysicist turned journalist. He has written for the Guardian, the Independent and Cosmos magazine. He writes about science and space for the Urban Times, and was previously the editor of those sections....

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