This is Scientific American's 60 Second Science. I'm Christine Herman. The angle has landed. July 20th marks 50 years since human beings first landed on the moon.

That momentous date in 1969 made astronauts Neil Armstrong and Buzz Aldrin household names.

But years before that, a lesser known figure was on a mission to make that first moon landing

possible.

His name was John Hobalt, the son of Dutch immigrants.

Hobalt grew up on a farm in Joliet, Illinois.

He studied engineering at the University of Illinois and eventually worked his way to NASA.

It was there in the early 60s that he put his career on the line to champion what was at the time an unpopular idea, but would ultimately be critical to getting Apollo 11 to the moon and safely back.

John faced a mixture of indifference, at times abuse and at times ridicule that he never

forgot until things started to change and engineers started to realize his data might be right.

Todd's Willick, author of the new audible original spoken word book about Hobalt's life.

It's called The Man Who Knew the Way to the Moon. So what was Hobalt's life, it's called the man who knew the way to the moon.

So what was Hobalt's unpopular idea?

He championed what's called Lunar Orbit rendezvous.

The concept involved sending a spacecraft into orbit around the moon, and from there sending only a small lightweight craft down to the moon's surface instead of the entire ship.

Zwilig says while Holbalt didn't invent the idea, he was the one who started to apply it

to the technologies that were within NASA's grasp at the time.

Most of the people who know the most about this mission

feel that without Lunar Orbit rendezvous, Apollo couldn't have succeeded.

And without John Hobold, you probably wouldn't have had Lunar Orbit rendezvous.

Zwillick's book also explores the kinds of challenges NASA engineers face today as they make

plans to get back to the moon and ultimately to Mars. When you talk about Mars, gosh

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