One message of this special issue is how, well, normal space exploration has become since Neil Armstrong and Buzz Aldrin landed on the moon almost exactly 50 years ago.

The number of satellites launched each year is shooting up as rockets get cheaper and satellites get smaller. Though only a few hundred people have been to space, billions depend on it: much of modern life would grind to a halt without GPS, satellite communications, and imagery from space. Apollo’s most important legacy, we argue, wasn’t that it put a person on the moon, but that it taught people to manage the kinds of gigantic engineering projects that have made those once miraculous technologies thoroughly mundane. Even a return visit to the moon, which could happen in the next few years, would now be a lot easier.

If once the biggest problems in space were how to get stuff up there, make it work, and bring it back, today’s problems arise because humanity has gotten all too good at doing so. There could soon be enough imaging satellites to subject everyone on Earth to constant real-time surveillance; there are fights over an increasingly crowded radio frequency spectrum; and it can only be a matter of time before someone acquires both the means and the motive to attack someone else’s satellite, potentially launching the first full-on space war.

But if some activities in space have become mundane, far more remain out of reach. Hence, the bulk of the stories here are about the miracles people are still trying to make happen. What makes space glamorous, after all, is not the mere act of getting to where no one has gone before, but the imagination, ingenuity, and hubris required to do it.

An aura of the mad genius who strives for what others would call impossible or foolish clings to many of the people you’ll meet on these pages. There’s Dave Masten and his crew, winning a NASA competition with a spacecraft cobbled together from, among other things, a discarded trash can lid. The people at Relativity Space, who’ve vowed to 3D-print virtually an entire rocket in 60 days. (Their CEO, Tim Ellis, is also one of our remarkable 35 Innovators under 35.) Breakthrough Starshot’s Philip Lubin, with his plan to use lasers to power a tiny probe to the nearest star at one-fifth the speed of light. Helen Hwang and her NASA team, who had to develop a heat shield to withstand energies no spacecraft had ever encountered. Valentin Glushko, the dean of Soviet rocketry, who doggedly insisted on designing an engine of a kind nobody else had built, which then powered US rockets after the Soviet Union collapsed. The visionaries—or, some would say, delusionaries—who saw a future in mining asteroids for profit.

Technology also leaves its mark on culture, so we’ve included brief excerpts of the best astronaut memoirs, a history of how the space age shaped rock music, and a science fiction story about a secret rebellion in a satellite cleanup crew.

The overall lesson, though, is a simple one: however routine some uses of space become, the things we can’t yet do there remain a source of wonder and inspiration. And those things can quite literally fill a universe.