Fifty years ago today, the Space Age gave birth to the age of satellite communication as we know it — though it wasn't clear at the time just how world-changing that outer-space angle would turn out to be. In retrospect, you could argue that the launch of AT&T's Telstar 1 satellite on July 10, 1962, made as much of a mark on the space frontier as Sputnik.

At the time, Americans worried that outer space was turning into a Cold War battleground, thanks to the Soviet Union's launch of the first-ever satellite (Sputnik in 1957) and the first human in space (Yuri Gagarin in 1961). "Only if the United States occupies a position of pre-eminence can we help decide whether this new ocean will be a sea of peace or a new, terrifying theater of war," President John F. Kennedy declared in 1962.

Telstar, the world's first commercial satellite, marked the shift from outer space's potential military applications to its peaceful uses — which is the way most people think of space ventures today. Within hours of Telstar's launch on a Thor-Delta rocket from Cape Canaveral, Fla., the satellite beamed a non-public test transmission from Andover Earth Station in Maine to the Pleumeur-Bodou ground station in France. Two weeks later, on July 23, it relayed the first-ever public, live trans-Atlantic TV signal, linking Europe and North America.

That was the start of something big.

"With Telstar and its successors, the world was made a smaller place, as billions of people around the world had instant access to news, sports and entertainment," Jeong Kim, president of Bell Labs, said in a statement marking the anniversary. "The phrase 'live via satellite' became part of the common vernacular. At the time, few people would have believed that 50 years later you could actually talk to your house or car, or predicted that children would play video games with other children 10,000 miles away."

Telstar 1 was capable of carrying just one black-and-white TV channel, plus 600 simultaneous voice calls. It was in operation for less than a year, but it blazed a trail for generations of satellites, including Telstar 18 in 2004.

"Today, as we celebrate the enormous achievement that Telstar represented, Bell Labs researchers are laying the foundation for communications and collaboration for the next 50 years," Kim said.

That vision includes satellite-connected digital personal assistants ... devices that can bring 21st-century medicine to anyplace on Earth or in orbit ... and avatars that can let Earthlings explore Mars from millions of miles away, through virtual reality.

Perhaps the biggest legacy of Telstar 1 lies in how it brought nations together 50 years ago, reassuring us that outer space really could be the "sea of peace" that Kennedy was aiming for. Will it always be that way? Please feel free to weigh in with your reflections on the anniversary in the comment space below.

More about satellite history:

• Sputnik started a satellite revolution
• America's space age turns 50
• How satellites saved the world
• Satellite still in orbit, 54 years after launch

The Smithsonian's National Air and Space Museum is presenting a "Telstar 50th Anniversary" symposium at the facility on Washington's National Mall at 1:30 p.m. ET Thursday. It will begin with a satellite TV connection to the Pleumeur-Bodou Telecommunications Museum in France, commemorating the first global transmission of a TV signal in 1962. Speakers include Wayne Clough, secretary of the Smithsonian; Francois Delattre, France's ambassador to the United States; and Robert Tate, U.S. consul for western France. Historians and experts from industry and government will discuss Telstar's impact. The symposium will be webcast via the Smithsonian's website. For more information, check Telstar50.org.

Alan Boyle is msnbc.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.