PORTLAND — Eugene Cernan used a few extra lunar maps, some light-stand clips and duct tape to make a fender for the rover he used to travel on the moon.

“Without it, the lunar dust would rooster tail up behind it,” Cernan said. “If we hadn’t been up there in person, an unmanned vehicle never would have been able to solve that problem.”

Cernan, 80, is a retired Navy aviator who — as commander of Apollo 17 in 1972 — was the last person to walk on the surface of the moon.

No matter how many remotely controlled unmanned vessels the National Aeronautics and Space Administration sends to Mars, Cernan said there’s no way to replace the ingenuity and resourcefulness of on-hand people in the exploration of the red planet.

That means in order to reach that frontier, school children have to get excited about it, he said.

“We need dreamers. We need the kids of tomorrow because they’re the ones who are going to take us back to the moon and on to Mars,” Cernan said. “We’ve got to get their attention and get them excited about learning.”

Cernan joined Karen McBride, who works on NASA’s Mars mission team, as speakers at Thursday night’s Champions for Kids dinner in Portland, benefiting the city’s branch of the Salvation Army. The annual dinner event is one of the organization’s biggest fundraisers of the year, and will allow the group to help provide programs and services for children in Greater Portland.

Cernan was born to blue-collar immigrant parents and grew up in the Chicago area. He said he’s still amazed he went from that modest upbringing to become one of 12 people to set foot on the moon.

In 2000, he wrote “The Last Man on the Moon,” a book about his experiences.

“I look back at that and say, ‘It’s a fantasy,’” Cernan said. “If kids look at that [story] 20 or 30 years from now and think they can do that, too, it’s worthwhile. If I can go to the moon, what can’t you do?”

Cernan said America’s space ambitions have fizzled in recent years, with President Barack Obama’s administration cutting funding for NASA’s return-to-the-moon Constellation program and growing tension with Russia, with whom the U.S. shares the International Space Station.

McBride said with those setbacks and others, it would be well more than three decades before the U.S. could feasibly send a person to Mars.

“I tell kids, ‘Even if it’s not space, don’t be afraid to try [to accomplish something great],’” she said.

Cernan suggested he’s frustrated that the country has strayed from its space exploration ambitions, but said he’s convinced one of today’s children will set foot on the red planet.

He turned his iPhone around in his hand and said, “There’s a thousand times more capability in this device than I had in my hands to get to the moon.”

“We are going to Mars. I promise you,” he continued. “I won’t be around to see it. But we can look at kids today and tell them with certainty: We’re going to Mars.”