50 years ago, NASA launched the Explorer 9 from Wallops Island, Virginia. It was one of many missions the space agency sent into orbit as the United States raced to catch up with the Soviet Union in the space race. Strapped to a Scout rocket, the Explorer was a prime example of a largely forgotten part of NASA's history: the inflatable spacecraft.
The first was the Echo 1, which you can see inflated inside the Navy's dirigible hangar at Weeksville, North Carolina. The reason for using inflatable craft is simple: they're light, which meant that you didn't need as much thrust from your rocket to get into orbit. John Pierce, Bell Laboratory's director of research in communication principles, and William O'Sullivan of the National Advisory Committee for Aeronautics became relentless promoters of the idea of balloon satellites for telecommunications and research. People called them -- seriously -- "satelloons."
The Echo satellite was made of aluminum-coated mylar and could be used a mirror to reflect communications signals around the globe. It carried only two FM transmitters, which you can see in the photo above as the round white blobs on the left and right near the balloons center. They were powered by 70 solar cells that fed storage batteries. The Echo was packed into a container 26 inches across and launched into space on a Thor-Delta booster rocket on August 12, 1960. After deploying in orbit, a pre-recorded message from President Dwight D. Eisenhower was bounced off the satellite.
"It is a great personal satisfaction to participate in this first experiment in communications. This is one more significant step in the United States program. The satellite balloon which has reflected these words may be used freely by any nation for similar experiments," Eisenhower said.
Amazingly, the Mylar balloon was able to survive in the harsh conditions of outer space, as American Heritage describes:
The seemingly frail balloon proved remarkably durable. Though "wrinkled like a prune" (according to press reports) by the tons of micrometeorites that hit, and eventually punctured, its thin skin, the weary traveler kept flying, broadcasting the first television pictures by satellite (images of a rodeo cowboy and a trained seal) in April 1962.
The satelloons proved the viability of commercial satellite communications, but they also were a little too difficult to work with to become more than experiments. Over the next several years, more satelloons were launched, although not as many as boosters might have envisioned. The very next one was the Explorer 9 and later its sister satellite the Explorer 24 (pictured below). They were research, not communications satellites, and contributed to our understanding of the Earth's atmosphere's properties.
More recently, a team in Romania is attempting to fly a balloon to the moon. No, really. Here's there balloon.
And a bonus pic. Here's the Weeksville, North Carolina, Navy dirigible hangar with dirigible instead of satelloons in it. Yes, it's awesome.
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