If Neil Armstrong had been sick on July 16, 1969, Jim Lovell, his backup, would have been shot into space and taken that “one giant leap for mankind.”

Instead, Lovell found himself watching the Apollo 11 launch at Cape Canaveral with famed aviator Charles Lindbergh. As Lovell mused about the world-changing effects of stepping foot on the moon, Lindbergh stopped him and said it was Lovell’s Apollo 8 journey — the first manned mission to leave Earth’s orbit and go around the moon — that was the bigger breakthrough.

“The last 60 miles (to the moon’s surface), Apollo 11 did it, 12 did it, 14 did it,” Lovell said. “But the initial approach outside of earth’s orbit (by Apollo 8) was the epitome of our program,” as Lindbergh saw it.

To mark the upcoming 50th anniversary of the Apollo 8 mission and celebrate Lovell’s legacy, the Adler Planetarium is giving him a lifetime achievement award at their Celestial Ball Saturday, and arranged a talk with reporters on Wednesday.

Lovell has a long relationship with the Adler, going back to his Boy Scout days when he would visit from Milwaukee to work toward his astronomy merit badge.

Now, Lovell has his own exhibit at Adler — Mission Moon. It tells the story of the Gemini and Apollo missions through the eyes of Lovell, featuring pieces from his personal collection, such as his NASA flight suit and salvaged items from Apollo 13, including mission manuals. Lovell said he took the curator to his basement, dusted off the artifacts and said, “which ones do you want?”

“I thought it was much better to have them in view where people could come down and see these things we had back in the Apollo and Gemini days than having them in my closet,” Lovell ssaid.

In addition to Apollo 8, Lovell was also part of the Gemini 7 mission, and is best known for his heroism and ingenuity in safely bringing Apollo 13 back to Earth after an explosion. Apollo 13 didn’t land on the moon as planned, but it did take the astronauts farther from Earth than any other human.

Lovell said he feels he was part of NASA’s “golden years,” and it’s been interesting to watch the space program evolve. He questions the efficacy of commercial space programs like Elon Musk’s SpaceX, but he’s excited by new space technology and the Curiosity and New Horizons rovers used to explore Mars and Pluto, respectively.

Sculpture of astronaut Jim Lovell at the Adler Planetarium

A sculpture of NASA astronaut Jim Lovell, depicted during the Apollo 13 mission he commanded, is part of the Mission Moon gallery at the Adler Planetarium. | Rahul Parikh/Sun-Times

Jim Bridenstine — the new NASA administrator and a fellow formal naval aviator — is a step in the right direction, Lovell said. He hopes he’ll emphasize more lunar missions to create technology and infrastructure to send people to Mars, and to further explore the moon itself: “We barely touched the surface of the moon,” he said.

Despite orbiting the moon twice, Lovell has never stepped foot on lunar soil. He said he used to regret never landing on the moon, but has since realized the importance of the “failed” Apollo 13 mission in paving the way for improvements in future missions.

And Lovell is still one of the first three people to orbit the moon. Lovell said he approached the Apollo 8 expedition differently from his crewmates. Frank Borman wanted to circumnavigate the moon as quickly as possible without taking any pictures. Luckily, Lovell and William Anders were able to talk him down, providing the world with the famous “Earthrise” picture.

“To me, this was a real adventure,” Lovell said. “It was like a mini Lewis and Clark expedition. I wasn’t there to beat the Russians, I didn’t really care if we beat the Russians or not. I was there because we were exploring new ground, new territory.”

With any expedition comes risks. After the accident, Apollo 13 had only a 50 percent chance of returning safely. And Lovell admits Apollo 8 wouldn’t have survived the technical malfunctions of Apollo 13. Before Apollo 8 departed, Lovell said his flight companions both wrote “farewell letters” to their wives in case something happened. Lovell didn’t. Instead, he told his wife “I’m coming back.”

His wife, Marilyn, sometimes chastises him for not leaving a letter, but Lovell arguably left her something better. His favorite item in the entire Adler collection is a photograph of a triangular mountain on the near side of the moon on the shore of the Sea of Tranquility.

“It looks on us every day and night, from the moon back to the earth,” he said. “I named it Mount Marilyn.”