When Sierra Gonzales was a girl, her grandmother often took her to the Fleischmann Planetarium on the campus of the University of Nevada, Reno. There, she marveled at the wonders of the universe; stars and planets filled her head – and maybe even an asteroid or two.
This week, a little more than a decade after those summertime excursions, Gonzales, 24, now a UNR graduate and a systems engineer, sits at a console in the Lockheed Martin Space Center in Littleton, Colo. On Oct. 20, Gonzales, in her role as “real time operator” of the spacecraft, gave the command that told a probe to snag a sample from the surface of Bennu, an asteroid 200 million miles from Earth.
“Copy. All systems go,” she said, after other team engineers reported that everything was in order for the sampling attempt. “The command will be radiated on my mark, 3, 2, 1 mark!” It was time for the “grab-and-go” part of the mission.
When the message from Earth reached the spacecraft, the collection chamber at the end of OSIRIS-REx’s 11-foot arm touched Bennu’s rugged surface. Decades of work by hundreds of scientists, engineers and specialists came down to just 6 seconds of contact with a tiny, distant world:
Playing tag with an asteroid
The rocks and pebbles that NASA’s OSIRIS-REx spacecraft scooped up are pieces of the 4.6 billion-year-old stuff the solar system is made of. The haul, when carried back to Earth, will help scientists unlock mysteries about how the solar system was born and, perhaps, how life got its start on our home planet.
Even at the speed of light, it takes 18 minutes for data to travel between the spacecraft and the earthbound control center. That was a lifetime of waiting for the engineers.
“It was eerily still as we were waiting for the telemetry to come down so we could see what the spacecraft was doing and where it was at,” Gonzales said. “Then, as the data came in little bits, there was some cheering. When we saw that it had contacted the surface and then backed away, it was pure joy! And there was relief swirling around. Our team worked really hard to get there. We were definitely pleased with the spacecraft’s performance.
“It was an exciting, unbelievable moment.”
A team effort put the craft in space
Hundreds of people at Lockheed Martin, the University of Arizona and the NASA Goddard Space Center labored for years to play tag with the asteroid.
“I’m just a small piece of this puzzle that made this all possible,” Gonzales said. “There are people (at Lockheed) who have been working for seven years, 16 years, most of their careers, to make this happen. I’m incredibly honored and lucky to be on this mission and learn so much as an engineer.”
The work they do in deep space supports life on this planet. “What we do really affects us here on Earth,” she said. “If we don’t look forward and dream big, we’re never going to be able to solve the everyday problems.”
A 7-year trip to Bennu and back
The $800 million OSIRIS-REx mission launched in September 2016 and arrived at the 1,640-foot-wide asteroid in December 2018. The asteroid’s orbit takes it between the orbits of Earth and of Mars. Bennu is around 100 million miles away from the sun.
Thermal imaging had led scientists to believe Bennu would have a smooth surface. But the asteroid was strewn with house-sized boulders and was a maze of sharp angles. They expected to find a landing spot akin to a beach at Pyramid Lake. Instead, what they saw looked more like the rocky features of Truckee River Canyon, writ large.
Avoiding ‘Mount Doom’ near the crater
The probe orbited the chunk of mineral-rich rock, searching for a landing site. After considering several possibilities, the team settled on a crater they dubbed “Nightingale.” It looked like a good choice, except for a nearby two-story boulder they nicknamed “Mount Doom.” From 200 million miles away, the engineers aimed for a target about 26 feet wide. The probe hit within 3 feet of the center of the bulls eye.
The mission was a success, but with an unforeseen glitch. The dinner-plate-sized collector scooped up some material that apparently caused the the containment flap on the device to remain open. Some of the rocks and pebbles were leaking into space. The Lockheed team is working to stow the captured material on board the probe and secure the sample for the journey home. OSIRIS-REx is scheduled to depart for Earth in March of next year. Its cargo should arrive in the Utah desert in September 2023.
Details, images and videos of the project are available online. One benefit of the project is the knowlege gained may help scientists better understand how asteroids move through space. That would help researchers determine the trajectories of potentially-hazardous asteroids, a category that includes Bennu.
It’s a long adventure for the spacecraft. Gonzales’ journey to the command center was shorter, but relatively fast. Her trajectory led from Reno to Colorado and (virtually) into deep space.
From Damonte Ranch to UNR to deep space
“I’m definitely a Northern Nevada girl,” she said. “…When I was little, we went to the planetarium all the time.” Seeds had been planted, but it would be years before space became her destination.
“She was always an engineer at heart,” said Gonzales’ aunt, Julie Machado of Reno. “She always wanted to know how things worked and how to make them work. When she was 4 she was putting together a barbecue grill in the backyard. But she’s also well rounded; she is interested in so many things.”
Gonzales is a swimmer and a musician. She plays the double bass with the Denver Pops Orchestra. She is a graduate of Damonte Ranch High School, where she first started thinking about an engineering degree.
“A teacher asked us what we wanted to do with the rest of our lives,” she said. “I thought, ‘wow, what do I really want to do?’ I loved math and science and music. I really wanted to something creative, but also to use math and science. I decided to go to school for robotics and hopefully do something in space, like the (Mars) rover — something out there on the final frontier.”– Sierra Gonzales, spacecraft systems engineer.
She majored in mechanical engineering at UNR and discovered her passion. “I loved engineering, the hands-on stuff and the programming,” Gonzales said. She earned a bachelor’s and a master’s degree in mechanical engineering. She taught 3-D printing at Truckee Meadows Community College, was a consultant in UNR’s robotics lab and a “tech wrangler” in the campus engineering library.
While in UNR’s accelerated master’s program, she served an internship at Lockheed in its Commercial Space Division. There, she toured the Deep Space area, where OSIRIS-REx was built. She liked what she saw; her excitement was off the scale.
“I thought, ‘I’ve got to do this.’ I want this job,” Gonzales said. “Before (the tour) I didn’t even know it was a job.” While still a graduate student she received the offer to work on the OSIRIS-REx program and joined the team about six months before the probe arrived at Bennu.
Results will benefit generations
“It was perfect timing to jump into all the exciting things and learn how to be a systems engineer,” she said. “In school, we learn how to solve problems, how to approach a problem and figure it out. That’s what we do here. How do you sample an asteroid? Your team figures it out together.”
The results of the mission aren’t just academic. “What are the benefits? What questions do we hope to answer? The big one is where do we (humans and life on Earth) come from? For humanity’s sake, that’s the question I always talk about.”
Asteroids may yield resources for explorers
The other side of the coin is the “RI” part of the probe’s name, which stands for “resource identification.” That goal is to find materials in space that future explorers will need to travel the vast distances involved. What is out there in space that spacecraft crews can use to build the things they need to explore distant celestial bodies?
“So the questions we hope to answer are about where we came from and where we’re going,” she said.
Gonzales has mountains of data ahead of her in her career and will be helping to solve technical problems that can’t be imagined today. If she had a chance to physically go where no person has gone before, would she step through a hatch, await liftoff and aim for the stars?
“Oh, yeah!” she answered without hesitation. “If you ask other engineers they might give you a 50-50 answer. Not me; I’ll go. I think it would be a one-of-a-kind experience.”