When the call from NASA came, Lt. Kayla Barron wasn't able to take it — or even hear it.
As an aide to the superintendent of the Naval Academy, Barron was on the review stand for the color parade, one of the highlights of commissioning week in Annapolis and held on May 25 this year, calling off the multiple gun salutes.
But when she got free, Barron learned the news: She was one of 12 members of NASA's newest class of astronaut candidates, selected from the space agency's largest applicant pool ever of more than 18,300 aspirants.
"I was just over the moon," Barron said Thursday.
Which is literally where she may be headed after two years of astronaut training that begins in August.
Barron, 29, a 2010 graduate of the Naval Academy, kept the news secret from all but a few family, friends and her boss, Vice Admiral Walter E. "Ted" Carter, Jr., the academy superintendent, who had encouraged her to apply.
"Flabbergasted," is how Carter described his reaction when his aide received the news from NASA that day. There were "some tears — and Kayla is not very emotional — and hugs for everyone. She's part of our family."
Like the rest of the astronaut class, Barron is rather intimidatingly accomplished.
She graduated fifth in her class of 1,051 Mids, with a perfect 4.0 cumulative grade point average.
At the academy — she was Kayla Sax then, having taken her husband's name after they married in 2013 — she was part of the Trident Scholar Program. The program allows top midshipmen to conduct research in their senior year, and her project focused on developing "a more affordable, low-powered, extremely sensitive neutron detection system," according to the academy.
After the Navy dropped the men-only restriction on submarine service, Barron was among the first class of 11 women from the academy to be commissioned as officers of what is called "the Silent Service."
Barron, who ran track and cross country all four years and edited at The LOG humor magazine at the academy, earned her bachelor's degree in systems engineering. She received a scholarship from the Bill and Melinda Gates Foundation to attend the University of Cambridge in England, where she earned a master's degree in nuclear engineering in 2011.
"The Gates Foundation believes science and technology have great potential to improve lives around the world, a principle that has always shaped my passion for engineering," she said in an academy news release announcing her receipt of the scholarship in March 2010. "Over the past few years, increased energy demands coupled with the need to address anthropogenic climate change have focused my interest on alternative energy sources, especially nuclear power."
Barron was initially interested in naval aviation, but didn't meet the stringent eyesight requirments. She checked out other career paths, and was drawn to submarine service, seeing it as suited to someone like her who enjoys working on "a small team in a high-stress environment."
"I really felt at home there," she said in a telephone interview from the Johnson Space Center in Houston. "I think we're all nerds of a certain variety. Everyone is really talented and team-oriented."
After her year in Cambridge, she moved to Charleston, S.C., for training as a submarine officer. In 2013, she was assigned to the USS Maine submarine in Bangor, Wash., which brought her back to her home state. She grew up in Richland in the southeast part of the state.
"It's an adjustment," she said of submarine life, especially given her height: 5-feet, 11-inches. "You'd be bumping your head, hitting your shins on things. But you'd be surprised at how quickly you adapt to a routine."
She also got married in 2013, to Tom Barron, a Harvard graduate and now Army Special Forces captain. They met as students at Cambridge.
In August 2015, she returned to the Naval Academy, becoming flag aide to the superintendent, Carter. She described the job as his military assistant and gatekeeper, handling scheduling and attending meetings with him.
Having served as an aide himself over the course of a Navy career that began when he graduated from the academy in 1981, Carter said he knew "she was the right person" when he interviewed candidates for the job.
He calls her "one of the most talented officers I've ever worked with" and predicts that "America will fall in love with her."
Carter remembers riding home from an event at the Smithsonian's National Air & Space Museum more than a year ago where he and Barron mingled with NASA officials and astronauts. In the car, Barron mused about what an astronaut's life must be like, Carter said.
"I challenged her," he said. "You apply."
Barron would be the 54th Naval Academy graduate to become an astronaut, the most of any school, Carter noted. She follows in the footsteps of legends like Alan Shepard, Wally Schirra and Jim Lovell.
As a submarine officer, Barron is in an even smaller class. Stephen G. Bowen, an Academy graduate who completed his NASA training in 2000, was the first submarine officer selected to become an astronaut by the agency. Michael J. McCulley, a Navy enlistee who served on three submarines before becoming a test pilot, became an astronaut in 1985.
"There's definitely some analogs" between serving on a submarine and in space, particularly on a long-duration mission to the International Space Station, Barron said.
"There are no port calls. ... All your tools are already on board," she said.
Barron and two other astronaut candidates are, at 29, the youngest of the incoming NASA class. The oldest is 42 years old.
"That's what made her stand out," Carter said he believes, "because of the tremendous amount of experience she has had for a young person."
Her father, Scott Sax, said he has a running joke with his daughter, her high school's valedictorian, about how accustomed she must be to always being number one. (She is, however, the middle of his three daughters with his wife, Lauri. The oldest is a doctor and the youngest a minister.)
When she applied to NASA, though, "her goal was just to be truly considered," he said.
After she was one of 120 to be selected to be interviewed, her goal shifted to becoming one of the finalists, said Sax, an engineer.
This spring, she was one of 50 to be interviewed again, Barron said.
"Like a good engineer, I was always doing the math in my head and calculating the probabilities," she said. "It seemed like a steep slope to climb."
Barron will return soon to Annapolis, where she lives downtown and likes to run and frequent "a lot of the restaurants," to finish a few tasks at the academy before starting astronaut training.
Among her NASA classmates are an Army surgeon, a veteran of multiple Antarctic expeditions, someone who is both an engineer at the private SpaceX and a former commercial fisherman, and a former Navy SEAL who is now an emergency room doctor.
As competitive as it is to become an astronaut, Barron said the process was actually collegial and supportive. It was "eye-watering" to learn about the backgrounds of the other applicants, and hear them talk about their goals. She never thought of them as competitors, but pottential teammates.
"You can't help but root for everyone," she said.