Fifty years ago, an amazing thing happened when two humans – Neil Armstrong and Edwin “Buzz” Aldrin – landed on the moon and stepped onto its dusty surface. The fact their craft didn’t hurtle to the ground and turn the moon into their grave was, in itself, hard to believe. And their return to earth alive, with orbiting module astronaut Michael Collins, only added to Americans’ joy and sense of accomplishment.

Advancements in computers, medicine, physics and the understanding of how space travel affects humans all have come in the years since the end of the Apollo program and our last moon landing. Much of the research continuing today takes place aboard the International Space Station or with data recorded and transmitted back to earth by unmanned satellites.

Although Elon Musk and others are pursuing the goal of human space travel run by private companies, NASA has been pumping billions into development of a skyscraper-sized Space Launch System that it hopes could take Americans back to the moon as early as 2024.

But, at a time when the earth is facing huge, ongoing environmental problems – from widespread ocean pollution, clearcutting and burning of rainforests, long-term damage from fracking and oil extraction, melting permafrost in the far north and loss of land from rising seas – it’s valid to ask why we should return to a place we’ve already visited?

Twelve men walked on the moon. Countless satellites have mapped it, photographed it, and done all manner of analysis of it. And, more importantly, space travel has gone far beyond the moon in the 50 years since Apollo 11. Roving robots are crisscrossing Mars, sending back photos and data about the soil, light, air and chemical makeup – giving us a great understanding of a planet no human has visited. The Hubble telescope sends images to earth of planets and solar systems far beyond anything we could ever visit. The manned International Space Station provides cell-level analysis of the impact of long-term space travel on the human body, not to mention insight into the dynamics of people living together in a finite space for months, or years, at a time.

Everything leading up to the Apollo 11 moon landing and all space exploration that has taken place since is important in the evolution and understanding of humans and where we are in time and space. There is growing support for using robots for future exploration – which is, in effect, what’s happening with the Mars rovers and satellites sent beyond our solar system. Robots are durable, expendable, “live” far longer than humans and can efficiently gather and transmit information 24/7, for untold years to come.

A major development in space exploration came when Musk and other entrepreneurs starting putting their money and ideas into development of rockets and technology that governments are using to resupply the space station and to launch private research and communications satellites. This infusion of private capital and ideas into what had been an expensive taxpayer-funded endeavor will continue to expand our boundaries, with or without humans on board.

Fifty years on, the planets and stars still grab our attention; developments in technology from space exploration continue to alter our lives. The debate about using robots, humans or both for space exploration will continue even as we grapple with the looming challenges of climate change and the struggles of humans to live here on earth. However the debate is resolved, there is unmistakable, immeasurable benefit to humanity from our more than 50-year quest to reach into outer space.

Old-timers remember well the face and voice of legendary newsman Walter Cronkite broadcasting during the Apollo 11 touchdown at Tranquility Base on that July day. As Neil Armstrong and Buzz Aldrin climbed into their lunar module on the first phase of the return of the three astronauts to earth, Cronkite said, “Apollo 11 still has a long way to go. And so do we.”

His words have as much meaning today as the moment when Armstrong’s boot first touched the lunar soil.