Fifty years ago today (April 12), cosmonaut Yuri Gagarin blasted into Earth orbit, marking the beginning of the human spaceflight era.
In humanity's first half-century as a spacefaring species, government-run space programs put people on the moon and began to master low-Earth orbit. The next 50 years should bring a sea change, with commercial companies taking over near-Earth operations and freeing NASA and other space agencies to send astronauts to asteroids and Mars.
As a result, by 2061, millions of people may well have gone to space, and thousands may be living there, experts say. We may see permanently manned outposts on the moon, and boots will likely have crunched into Mars' red dirt.
April 12 marks two huge milestones in the history of human spaceflight. On that date in 1961, the Soviet Union's Yuri Gagarin became the first person in history to reach outer space. And exactly 20 years later, NASA launched the first space shuttle mission, debuting the workhorse vehicle that would carry astronauts to and from low-Earth orbit for the next three decades. There have been a lot of other "firsts" in the 50 years of human spaceflight.