In 1996, Endeavour released a coffee-table-size package that inflated into a 46-foot antenna; the tennis-court-size structure worked for several hours in space

There seems to be something quite charming about the thought of the spacecraft launching an apparatus that can fold up to be the size of a coffee table, only for it to unfold into the size of a tennis court when it finally goes into space. Sounds almost like the plot of a cartoon movie, but it really did happen aboard the NASA space shuttle Endeavour. The NASA Jet Propulsion Laboratory has classified this small package as the Inflatable Antenna Experiment, which became a 46-foot-wide, 98-foot-long mylar antenna once it was in space. This story also offers insight into why the people who built its equipment felt such affection for Endeavour. The space shuttle made twenty-five trips into space from 1992 to 2011, spending 299 days in orbit and travelling 122,883,151 miles before being retired and placed on display at the California Science Center in Los Angeles.

On its final journey home in September 2012, Endeavour flew low over several Los Angeles landmarks, including the Jet Propulsion Laboratory, giving the engineers who worked on its payloads one last chance to watch it pass overhead. Endeavour was the final shuttle built, assembled from spare structural parts as a replacement for Challenger, and it took its name from the British sailing ship HMS Endeavour, once captained by James Cook on his first voyage of discovery.

Bigger than a tennis court


According to the laboratory's own account of the mission, the Inflatable Antenna Experiment flew in 1996 and remains one of the more unusual stories from Endeavour's long career. It was built by LaGarde in Tustin, California, managed by the Jet Propulsion Laboratory, and mounted on the Spartan-207 satellite. Once released, the inflatable structure deployed to 46 feet in diameter and 98 feet in length, making it larger than a tennis court. JPL described it as the largest structure ever erected in space at the time, until the Shuttle Radar Topography Mission surpassed that record in 2000. The project's manager later recalled that the team ran outside Mission Control in Houston to watch Endeavour and the deployed antenna pass overhead, calling it one of the highlights of his career. The demonstration was designed to test inflatable reflector antenna technology in space, showing that a large structure could be launched in a compact form and deployed in orbit. The antenna operated for several hours before the demonstration ended.

More than one clever idea on board

The inflatable antenna was far from the only interesting payload Endeavour carried into orbit, and JPL's mission archive lists several others that help explain the deep affection the shuttle earned among its engineers. In 1993, it carried the Wide Field and Planetary Camera 2, nicknamed The Camera That Saved Hubble. The instrument corrected a flaw in the telescope's main mirror and went on to capture more than 135,000 observations of the universe over almost sixteen years. In 2000, it flew the Shuttle Radar Topography Mission, an 11-day flight that produced the first detailed near-global topographical map of Earth, covering close to 80 percent of the planet's land surface. One scientist described it as probably the most significant mapping mission of any kind attempted at that point. Earlier still, in 1994, the shuttle carried a radar instrument known as SIR-C/X-SAR on two separate flights. According to the laboratory's records, it was used to study soil moisture, ocean behaviour, volcanic activity and shifting tectonic plates, and it captured the most detailed documentation of a volcanic eruption seen from orbit up to that time. A quieter experiment flew alongside the inflatable antenna during that same 1996 mission: the Brilliant Eyes Ten-Kelvin Sorption Cryocooler Experiment, which used a vibration-free refrigeration method suited to delicate instruments and reached 10 Kelvin. That cooling technology later helped lead to two sorption coolers used to chill highly sensitive infrared sensors on the European Space Agency’s Planck mission, which sought answers about the early history and evolution of the universe. A shuttle assembled from spare parts ended up carrying one of the most surprising experimental structures of its time, packed into a coffee-table-sized container before unfolding into something far larger in space.