NASA Hopes Smaller Is Better

Scientists at NASA's Goddard Space Flight Center on Monday unveiled new satellites that may well represent the future of space science -- they're about the size of a microwave oven.

 The agency's $130 million Space Technology Five mission will test three micro-satellites designed to measure the earth's magnetic field, track the solar storms that batter it and serve as prototypes for probes that can predict solar hurricanes the way forecasters now predict the weather on earth. 



 In February, a single rocket will launch the micro-satellites into polar orbits, up to 2,800 miles high, where they will take measurements for 90 days before eventually burning up. The mission, planned since 1999, will test the miniaturized monitoring and communications technology that the National Aeronautics and Space Administration hopes to use for years to come in instruments ranging from weather satellites to space telescopes. 



 "The first priority is validating the technology we've developed," said Candace Carlisle, the mission's deputy project manager. Carlisle said the satellites' diminutive size is what sets them apart from other probes -- smaller devices mean smaller, more efficient payloads, she said. 



 The ultimate goal is to send dozens of such satellites into space, at a cost of $1.5 million each, to keep an eye out for solar storms. "We want to show that these small systems can do useful science," she said. "We think that's where the future is." 



 Everything on ST5 is as small as possible, with equipment squeezed down to as little as 25 percent of its normal size, Carlisle said. 



 The transponder, a communications system that relays data to earth, is about the size of an egg. The magnetometer, which will measure the intensity of magnetic fields above the north and south poles, is a two-inch thick pancake with the circumference of a tennis ball. It extends outward from the main satellite on a small arm. 



 Weighing only 55 pounds, the hectagonal cylinders are about 19-inches tall and 20-inches wide. By comparison, the average NASA spacecraft weighs 1,000 to 2,000 pounds (they come in a variety of shapes and sizes). 



 Once launched on a Pegasus XL rocket, the new satellites will be flung frisbee-style from the rocket, so they orbit about 50 miles apart. 



 The mission is called Space Technology Five because it's the fifth mission in NASA's New Millennium Program, an initiative created to develop and test new technologies. 



 NASA hopes the probes will eventually warn us earlier and minimize the threats posed by solar hurricanes, which can disrupt radio communications and knock out Global Position systems and power grids. 



 NASA has launched several earlier probes that monitor for solar storms and the forces that create them. The Advanced Composition Explorer, launched in 1997, studies energetic particles from the sun. The Transition Region Coronal Explorer, launched in 1998, studies the links between the sun's magnetic fields and the heating of the Sun's corona. 



 But solar storms themselves are still hard to predict, and ST5 will test technologies that should be able to provide the best measurements yet of the Earth's magnetic field and track the storms that enter it, said project scientist James A. Slavin. 



 "We'll be able to measure these structures as they occur, in the solar winds, so we can predict when they will occur and where they will hit," Slavin said. 



 The probes will depart from from Vandenburg Air Force Base in California Feb. 28 and head for polar orbits so they can measure the electromagnetic field in the currents of the Aurora Borealis, where the field is most evident. 



 Auroral displays are common in far northern latitudes. But unusual solar storms -- such as some last November -- have been known to push them farther south. 



 The sun is constantly hurling solar flares, creating solar hurricanes or assembling coronal mass ejection's in space. 



 The storms can send bolts of magnetic energy and billions of tons of electrically charged particles into the magnetic field that surrounds and protects the earth from solar radiation. Such blasts can rattle the magnetic field, causing geomagnetic storms that trigger electrical surges in long-distance transmission lines and disrupt high-frequency radio and navigation systems. 



 A solar hurricane in 1989 blacked out much of Canada and the Upper Midwest. One on Halloween 2003, knocked out GPS systems and power grids.