How did Orion withstand temperatures twice the melting point of steel?

Meet Molly White, the engineer who helped make it possible

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In Florida, at the Kennedy Space Center, Molly White is cheering with her sister. Today the two space enthusiasts watched gleefully as the Orion spacecraft rocketed away from Cape Canaveral, circled Earth twice, and splashed down off the coast of Baja California in the Pacific Ocean at 10:29AM Eastern. A product of years of work and anticipation, the uncrewed Orion Exploration Test Flight-1 took exactly 4 hours and 24 minutes. And White, an aerospace engineer for the National Aeronautics and Space Administration, was crucial to making it all work.

molly and emma white

Molly White, left, and her sister Emma at the Kennedy Space Center causeway viewing area just before launch. (Image courtesy Molly & Emma White)

"It was indescribable," she says. "The crowd got quiet during the countdown, we were all holding our breath, hoping nothing would go wrong. And when it went off it was so loud, so huge. It was just amazing."

White is one of the many researchers responsible for Orion’s heat shield. This reflective, flammable blanket is crucial to the spacecraft’s ultimate mission: sending humans to Mars and bringing them back safely. It’s been White’s job since 2010 to predict temperature and airflow around the heat shield during takeoff and landing.

She’s been counting down to today for months. "These last few days have just been watching, waiting, and getting more and more excited," she says. Yesterday, the intended launch was repeatedly delayed by stray boats, wind gusts, and technical problems — and that was "a bit of an emotional roller coaster," she says. "It goes to show you so many things have to go right for a space launch – the weather, all of the systems, the rocket, as well as the payload."

"I’ll be high off of this for a few weeks," she says. Like a lot of kids, she wanted to work for NASA. As a little girl she admired her grandfathers, who were both engineers. In school she excelled in math and science and started to love space after a middle school project on the cosmos. She studied aerospace engineering, hoping to work on spaceflight. "Part of me thought it was a pipe dream," she says, "something I’d never get to work on."

The first day on her dream job was actually a let-down. On February 1, 2010 — her first day — NASA’s Constellation program, the George W. Bush-era plan to return humans to the moon via Ares I and Ares V rockets, was cancelled. "I had been brought on to help with Constellation, so I was a bit nervous," White says. Her boss assured her though that something new and cool would be coming her way. She’s worked on Orion ever since.

the first day of her dream job at nasa was actually a let-down. the project she had been hired for was cancelled.

Today’s test flight is crucial for her to continue her work. After all the data is recovered White and her team will have a lot of work to do evaluating how well their predictions stacked against the harsh reality of space.

orion heat shield is installed

The largest-ever heat shield is installed on Orion. (NASA)

"There is a lot at stake for this flight test because we really need this data to refine our design and to know how the parts of Orion perform together," White says. "We have our models and our simulations, and while we do the best that we can, there could be parts that we missed or didn’t know existed. You can’t know what you don’t know, right?"

NASA has sent humans beyond Earth many times, notably during 11 Apollo moon missions between 1968 and 1972. But Orion is to be the most ambitious crewed mission to date, representing a renewed hunger for space exploration. This spacecraft is meant to travel farther, faster, and carry more astronauts than ever before, and it’s hoped that Orion will be the safest space vehicle built to date. If all goes according to schedule, Orion will put humans on an asteroid by 2025 and on Mars in the 2030s. Here’s how crazy it all is: in June, a blue-ribbon panel issued a highly critical report, questioning whether the agency was currently on the right track. The congressionally charted Committee on Human Spaceflight suggested focusing more exclusively on reaching Mars. In response, NASA essentially yawned.

orion could put humans on an asteroid by 2025 and ON MARS IN 2030-2040

Orion bears a striking resemblance to the Apollo crafts, and that’s no mistake. "The theme of Orion is recreating Apollo with 21st century modern technology," says John Balboni, an engineer at the NASA Ames Research Center. Balboni has worked in the arc jet test facility for the past 30 years, testing heat-shielding materials in a plasma wind-tunnel.

earth view

A view of Earth from Orion's first orbit. (NASA)

"We can’t just reuse the old designs," he says. The engineers who created materials such as the Apollo heat shield left documentation, but few of them are around anymore. "It’s like trying to make a cake from your grandmother’s recipe," he says. "She could leave you all the ingredients and all the steps, but you’re not going to make a cake as good as your grandmother made."

That’s not all. In the decades since the Apollo missions, new materials, such as high-temperature ceramics, have been invented and some old materials have been improved. Other components used years ago, such as asbestos, were phased out after they were found to be toxic. For Orion’s shield NASA redeveloped Avcoat, a combination of fiberglass and high-tech plastics, that was used, in an earlier form, for Apollo’s heat shield.

"IT'S LIKE TRYING TO MAKE A CAKE FROM YOUR GRANDMOTHER'S RECIPE."

The shield is crucial to the success of the mission because getting humans into and home from deep space requires hurling them around as fast as possible. The faster a craft’s trip through the atmosphere, the more kinetic energy is transferred into heat. A capsule returning from the moon smacks into the atmosphere at about 25,000 miles per hour. The heat shield reaches about 5,000º F at this speed. If Orion makes the return journey from Mars someday, it’ll enter the atmosphere at an estimated 33,500 miles per hour, heating the heat shield to near 5,500º F. The air around it, as it travels in a plasma fireball, is about twice as hot as the surface of the sun.

That much heat puts intense stress on materials, and if your heat shield fails, the entire vehicle can be lost. "We’ve seen failures of the heat shield on the shuttle mission," says White. "Hot gas was able to get inside the structure and cause things to explode and burn up." In 2003, space shuttle Columbia disintegrated as some of heat-protective tiles failed just before landing, killing all seven crew members aboard.

Today, after saying goodbye to Florida, Orion sped through the atmosphere. On the surface of the craft, the noise was estimated to be about 100 times louder than a rock concert. Orion circled the earth twice, reaching as high as 3,600 miles on the second loop – 15 times higher than the International Space Station. When Orion slammed back into the atmosphere at 20,000 mph (about 30 times the speed of sound) the heat shield survived an estimated 4,000º F. If it worked as intended, about 20 percent of the shield burned up on the way down, further dissipating heat.

"the most perfect flight you could imagine."

After about five minutes into its ride through the atmosphere, slowing down to about 300 mph, Orion began firing parachutes. These parachutes, 11 in total, unfurled in a multi-stage Kevlar-nylon ballet. With their help, Orion decelerated from 300 mph to just 20 mph in five minutes, slow enough for a graceful splashdown.

"It turned out to be the most perfect flight you could imagine," said Rob Navias, NASA TV commentator as Orion splashed down.

The spacecraft is now floating in the water, soon to be recovered by two US Navy ships. The USS Anchorage will collect the crew module, while the salvage ship, the USNS Salvor, will recover jettisoned hardware like parachutes and the forward bay cover, which protects the upper part of the spacecraft.

I get a text from Molly just after the splashdown. ""We made it!!" she writes.

The precious data White wants is now bobbing in the Pacific, aboard the crew module. More than 1000 sensors aboard Orion recorded conditions during the flight: the stress, vibration, temperature, acceleration, pressure — all the crucial information to prepare for a flight that will include people. It’s been an exciting day for White. She and her team will spend the day basking in the glow of a successful test. But Monday she goes back to work. After all, Mars is still a long way off.