LOGAN, Utah -- Innovative small satellites continue to make headway but have yet to disrupt the markets dominated by their larger, more complex and more costly counterparts, according to experts at the 18th annual Conference on Small Satellites held here Aug. 9-12.

The conference, sponsored by the American Institute of Aeronautics and Astronautics and Utah State University, played host to a continuing debate over whether small satellites will evolve to replace large satellites or to complement them.

Andrew Lewin, a program manager at the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., told the conference that small satellites do conduct valuable missions, but they represent only a small part of the overall space market and do not appear to be poised for substantial growth.

"Small satellites will continue to demonstrate considerable utility, but not necessarily reach the threshold of being disruptive technology," Lewin said.

Lewin said the type of innovation necessary for small satellites to disrupt the status quo would come from the commercial market. "In my mind, that's really where it's at," he said.

"Big satellites, right now, the way we do it, they are hard and they are a pain. But they're the only game out there," Ganley noted. He said small satellites could have a growing impact on the market if they are made simpler, cheaper and more modular than larger spacecraft -- with modularity achieved via accepted and utilized standards.

"I think there's something that we can learn as technologists, as engineers and scientists. It's not all about the technology," Ganley said. "The market forces really do matter. It's something that we have to pay attention to... if we ignore it, we do so at our peril," he concluded.

Tony Tether, director of the Defense Advanced Research Projects Agency (DARPA), told conference attendees, "DARPA is back in space in a big way."

Tether detailed the role of microsatellites for research, development and demonstration of concepts, devices and systems that provide highly advanced military capabilities. He said DARPA's space projects are focused on five areas: rapid, flexible space access; space-based support of tactical operations; active and passive defense of space assets; situational awareness of space; and space mission denial.

"We have a sizeable program," Tether continued, "on the order of probably three-quarters of a billion dollars in space in those five areas, most of it oriented toward microsatellites."

Robert Meurer, technical chairman of the conference and an international sales specialist based in Leesburg, Va., said the U.S. military's growing space requirements appear to be an emerging application for small satellites. "That might be the nugget here, and that might be the first place we really earn our stripes," he said.

Maneuverability in orbit could be a key technological advantage for small satellites, he said. "We need to mature small satellite propulsion technologies. We've had lots of papers but not a whole lot of real progress," he said. "Small satellites can really ruin the whole day of some bigger systems with some fairly dumb applications. It doesn't take a rocket scientist to figure out that you could release a bunch of ball bearings in an orbit and ruin the days of a whole lot of other satellites."

Three recent missions highlight the steady progression of scientific data gathering and technology testing via small satellites, according to Jan King, chief executive officer of Southern Cross Space & Communications Pty. Ltd., Weyba Downs, Queensland, Australia. The three missions are Canada's Microvariability and Oscillations of Stars microsatellite; Australia's FedSat; and NASA's Cosmic Hot Interstellar Plasma Spectrometer mission.

King said the cellular telephone and laptop computer markets are producing miniature technologies useful for small satellites.

As for a technology likely to affect small satellites in the coming years, Sweeting looks to micro-electro-mechanical systems, or the integration of mechanical elements, sensors, actuators and electronics on a common silicon substrate through microfabrication technology.

Regarding killer applications for small satellites, Sweeting said SSTL work in earth observations is clearly disruptive to the traditional way of carrying out remote sensing tasks using far heftier spacecraft.

As for the spirited nature of small satellite development, there are layers of cooperation and competition, Sweeting said. When small satellite applications enter into the commercial strata, he said, that makes it a business and that means competition.

"We've been doing this a long time and built up a big body of experience, doing new things year on year. I don't see it so much as a race, and we watch what other people do," Sweeting said. "We always look over our shoulders. Anybody with any sense is going to do that."