Lily Koppel is the author of "The Astronaut Wives Club," the book that inspired the ABC television series.

Astronaut John Glenn rides in an open car with his wife, Annie, during a ticker-tape parade in New York on Nov. 16, 1998. (Reuters/Mike Segar/file)

In April 1959, NASA revealed its first spacemen, the Mercury Seven astronauts, during a news conference in Washington, D.C. They became America’s first reality stars, their lives documented by Life magazine for a sum of $500,000 a piece. It was an unprecedented time. The new silver-suited space cowboys, who mostly came from military test-pilot backgrounds, became instant sex symbols, and John Glenn was the poster boy.

A model among the highly competitive group, Glenn even looked like the kid from Mad Magazine, freckle-faced and all-American. But what really set him apart from his fellow astronauts was the special relationship he had with his wife, Annie, even among the tremendous scrutiny and pressures that killed most of the astronauts’ marriages.

When I wrote my book on the astronaut wives, I learned that the Glenns were what NASA wanted all seven astronauts and their wives to be. They had what appeared to be the most solid love story in America, then and up until Thursday, when Glenn died at age 95.

When the space program began, the Glenns decided that John should throw his whole being into it. The plan was that Annie and their two kids would remain in Arlington, Va., and John would live at Langley Air Force Base, 120 miles away. He spent weeknights at the base’s Bachelor Officers Quarters, his monk-like room furnished with training manuals and a well-worn Bible. In the age of martinis and cigarettes, Glenn opted for oxygen, regularly donning his gray sweat suit and heading out for a jog.

Every weekend, John drove home to Annie and the kids (and their dog Chipper) in a clunker that got terrific gas mileage. The other hotdog astronauts teased him about the car. Most of the guys were big racers, loved fast cars and were planning to realize their hot-rod fantasies with the money Life magazine paid for exclusive coverage of their space adventures and family lives back on Earth.

It was nearly impossible to live up to the Glenns. The seemingly perfect couple had known each other all their lives, having met when they were just toddlers in their home town of New Concord, Ohio. Annie’s dentist father, Doc Castor, stuck her in a playpen with little “Johnny” during their local teetotalers’ monthly dinner club potluck. They were playmates throughout childhood, steadies later on and eventually married in April 1943.

The marriage lasted a lifetime. John called Annie his “rock.” She was his launch pad. Splashy color photos in Life featured her in a cherry print headscarf, steering a ski boat while John waterskied across Chesapeake Bay, a more middle-class version of Sen. John F. Kennedy’s family at Hyannis Port.

But life wasn’t all sugar. Annie suffered from a terrible stutter, and she famously didn’t let Vice President Lyndon B. Johnson, chairman of the National Aeronautics Space Council, come visit her at home for the TV cameras when John’s flight was scrubbed due to bad weather.

When Glenn finally boarded the Friendship 7 — the astronauts nicknamed their flimsy-looking capsule “the can” — in February 1962, he and Annie enacted a routine they’d been following since his earlier flying days and when he left to serve in World War II and Korea. Phone talk was not easy for Annie, so there wasn’t a whole lot of chatter.

“I’m going down to the corner store to buy some chewing gum,” Glenn said.

“Don’t take too long,” said Annie.

It was their way of acknowledging the understated fear that all the astronauts and their families lived with: that something could go wrong on the launch pad, where early test flights had blown up, or there could be a problem in space and NASA would be unable to bring the ship home.

In addition to the physical dangers, there were the dreaded astronaut groupies. The women, who hung out in Cocoa Beach, near where the rockets took off from the pad at Cape Canaveral, were known by the adorable (and, for the wives, maddening) moniker of “Cape Cookies.” They turned up in California, too.

Glenn, one of the only non-philandering astronauts among a group that would later include dozens more, always worked to motivate the rest of the guys — not only to work hard, but also to keep their pants zipped. Famously, he had a standoff with Alan Shepard (who won the prize to be first man in space, while Glenn was the first man to orbit the earth) on a trip to San Diego.

Most of the men figured that volunteering to be human cannonballs, who never knew if they would return, entitled them to blow off some steam. These astronauts had gone from being mostly anonymous American citizens to rock stars overnight, and suddenly women were dying to get near them, touch them. It was tolerable to NASA higher-ups as long as it stayed behind closed hotel doors, but one night, NASA’s press agent, a man named Shorty Powers, got wind of Shepard’s extracurricular activities. A reporter knew and had threatened to go public with the news. Glenn was called in to save the day.

The next day, Glenn laid down the law in one of the group’s closed-door meetings known among the Mercury Seven as an “séance.” The gist was that they were picked not only to get an important job done, but also to be American heroes. Shepard was putting a stain on the godly image. That was Glenn, an American hero who also knew he had a role to play. He carried this sense of purpose as a Democratic senator from Ohio and even ran for president in 1984, after which he went to work as an executive for R.C. Cola.

He returned to space in 1998, after which Annie told her husband she wanted him grounded, or home for good.

John Glenn will always be remembered for his accomplishments in space, but it was the man inside the spacesuit, fueled by the unique closeness and longevity of his marriage in an era that did not always celebrate marital partnership, who was the real hero.