Sometimes planetary exploration can be done on the "cheap" - at least without costly rockets and spacecraft. Earth is, after all, a planet thus we can explore our own world with a variety of tools on the ground and in the air.
Recently, I discussed exciting human ballooning feats at the edge of space in the 1950s and 1960s. Stratospheric ballooning has now become a robotic undertaking. While decidedly less inspiring than human-piloted adventures, a new generation of pilotless balloons will be launched skyward to explore where our atmosphere ends and the outer space begins.
Last month, NASA researchers successfully launched a prototype of a weird gasbag into the stratosphere above Antarctica. The event took place at the U.S. scientific base at McMurdo Station.
The one-third size balloon reached altitude at 111,000 ft. So far, things look good and the helium-filled gasbag is circling the South Pole, some 20 miles below.
According to a NASA news announcement, the same researchers hope to launch a titanic version of the test gasbag - a huge, pumpkin-shaped balloon constructed of plastic clingfilm - just like kitchen Saran Wrap. The aerostat (a technical term for a lighter-than-air craft) will drift along the fringe of space, for months on end, carrying a one-ton, pilotless instrument gondola.
NASA's new balloons are called super-pressure aerostats because they use the helium lifting gas at small amounts just above ambient pressure. According to David Pierce, who heads NASA's aerostat research laboratory at the agency's Wallops Island Facility on the Virginia coast - a place where atmospheric studies are conducted using small research rockets and weather balloons - these giant aerostats are "essentially very large pressure vessels."
Made of thin lightweight polyethylene film, the balloons are no thicker than ordinary plastic food wrap. Without some reinforcement, the aerostats would burst. So NASA designed "tendons" made of zylon plastic to hold the aerostat together.
Pierce told reporters that last month's South Pole test paves the way for at least 100 flights; flights that will loft large, heavy payloads to the edge of space within a year.
NASA's fleet of helium-filled pumpkins won't be alone at the South Pole. Antarctica is an ideal place for all kinds of balloons and atmospheric research.
A University of Maryland team recently launched its fourth Cosmic Ray Energetics and Mass aerostat (CREAM-4) from the South Pole, too. The CREAM-4 experiment collected energetic cosmic particles that were blown off distant supernova star explosions.
Thanks to technology employed by the nation's space agency and institutions, a 200-year-old aviation idea has been reinvented. Within a few months, high-tech robot balloons laden with scientific instruments will be flying regularly at the lonely edge of space.
Louis Varricchio, M.Sc., is a former NASA senior science writer. He is a member of the NASA/JPL Solar System Ambassador program in Vermont and a senior member of the U.S. Civil Air Patrol. Varricchio's second book, "Seeing Stars", will be published by Xlibris/Random House in late 2009. Portions of the forthcoming book will be illustrated by award-winning Middlebury artist Thomas Sinacore.