April 12th is a pretty momentous day for space nerds. Fifty-two years and one day ago, a mere handful of test pilots had flown above 100,000 feet. In 1960, Joe Kittinger jumped out of a balloon 102,800 feet above New Mexico. A year prior to Kittinger’s jump, "Joe" Jordan flew an F-104 starfighter to 103,389 feet, and in 1956 Iven Kincheloe took the X-2 as high as 126,283 feet. But the border between our atmosphere and space (known as the Karman line) was two and half times higher, 60 miles (or 328,000 feet) above ground. The USSR and USA had launched a number of satellites above the Karman line, but April 12th, 1961 was the first time one of these rockets had a human being sitting in it.

At a little after 9am local time, Yuri Gagarin became the first person in history to leave our atmosphere, riding Vostok 1 into orbit. The modified R-7 ICBM took off from the Tyura-Tam ICBM test site, located on the remote and desolate Khazak Steppe, and 108 minutes later Gagarin returned to Earth, landing nearly 1,000 miles away, near the Russian city of Engels. If 1957’s launch of Sputnik 1 had started the space race between the US and USSR, Vostok 1 and the first manned orbit solidified the Soviets’ position in the lead. The next decade would see tremendous progress by both nations, culminating in 1969, when Neil Armstrong set foot on the moon.

Gagarin’s flight alone is enough reason to celebrate April 12th, but 20 years later to the day, astronauts John Young and Bob Crippen took the Space Shuttle Columbia on its maiden voyage. The Space Shuttle, unlike all the manned spacecraft before it, was reusable, and with claims of routine, weekly launches costing as little as $20 million a shot, it was supposed to usher in a new era of spaceflight.

Sadly, that didn’t turn out to be true. Five years and 24 flights later, the Space Shuttle Challenger was destroyed 73 seconds after launch, killing all seven astronauts on board. The Shuttle fleet was grounded for nearly three years, until September 1988 when the Space Shuttle Discovery returned astronauts to orbit.

Shuttle launches never became as cheap and routine as promised, but they continued at the rate of 6-8 a year until 2003, when Columbia and the seven astronauts aboard it were lost on reentry. The investigation into the loss of a second Space Shuttle laid the blame as much on "a flawed NASA culture that downplayed risk and suppressed dissent" as on the foam-damaged wing, leading NASA’s then-chief, Michael Griffin, to call the Space Shuttle program a mistake.

But April 12th is not a day for mourning the Space Shuttle, it’s a day for celebrating spaceflight. Across the world, people will celebrate Yuri’s Night, first held in 2001 on the 40th anniversary of Gagarin’s orbit. If that sounds like something you might be interested in, what better way to get in the mood than by taking a dive into our archives with some great space content? See Matt Ford’s excellent 30-year Space Shuttle retrospective, for instance, or my trip to see the final Shuttle launch. What about a virtual tour through Kennedy Space Center? Even though the Space Shuttle flies no more, find out why reusable spacecraft aren’t dead as a concept, and how astronauts still train for space in a giant swimming pool in Texas.

If you’re lucky enough to live near one of the retired orbiters, this weekend could be a great time to go see one. Discovery is located in DC at the National Air and Space Museum, Endeavour is at LA’s California Science Center, Atlantis is at Kennedy Space Center in Florida, and Enterprise is in NYC’s Intrepid Sea, Air, and Space Museum. And for the bookworms among you, NASA has kindly made the English translation of Rockets and People, Boris Chertok’s excellent memoirs about the Soviet rocket program, freely available as e-books.

No time to read? Fear not! How about a video of every Shuttle launch, at the same time?

Or check out this rather excellent footage from the Shuttle’s solid rocket boosters, from launch to splashdown.

Happy birthday, spaceflight!