LOGAN, UTAH -- Innovative small satellites continue to make headway in usurping their larger, more complex and costly counterparts, but remain "utility-challenged" in the quest to match or disrupt conventional ways of carrying out space missions.

Small satellites typically fall into the range of 500 kilograms to 600 kilograms. These spacecraft embrace cutting edge or commercial off-the-shelf technology, permitting novel and less-expensive ways to perform meaningful space operations.

The debate is on as to whether small satellites will replace large satellites or complement existing technology. That discussion took center stage here as world experts met at the 18th annual Conference on Small Satellites, held August 9-12 and sponsored by the American Institute of Aeronautics and Astronautics and Utah State University.

"Small satellites will continue to demonstrate considerable utility, but not necessarily reach the threshold of being disruptive technology," said Andrew Lewin, a program manager at the Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland.

Lewin outlined results from an assessment done this year on the role small satellites play in military, civil, and commercial space sectors. The analysis shows that while small satellites do enable valuable missions, they represent only a small part of the overall space market. While there are some upcoming opportunities for small satellites, they do not appear to be poised for substantial growth in any of the markets, he reported.

Small satellite buzz words like "disruptive", "transformational" or "complimentary" are overused and bandied about yearly, but do have a genesis in something real, said Martin Sweeting, Director of the Surrey Space Centre and CEO of Surrey Satellite Technology Limited (SSTL) in Guildford, Surrey, United Kingdom. SSTL has been a notable and pioneering leader in innovative small satellite engineering.

Microsatellites are indeed disruptive, Sweeting said, specifically pointing to the impact of smaller spacecraft on the market model within the European space industry. However, the concept that disruptive means totally wiping away everything that went previously and replacing it with something new, "that's probably going a bit far," he advised.

"By about the year 2000, small satellites went from being a curiosity to something that was actually doing a useful job," Sweeting explained, thanks to linking up with commercial, off-the-shelf components stemming from the leisure market. Computer processors, imaging cameras and other consumer-driven technologies are making small satellites more and more capable, he said.

But small satellites are presently not a transformational technology, countered Lewin. However, he believes they can attempt to claim the title in three ways: Displacement of larger spacecraft; maintenance of existing market share within a growing space market; or creation of new markets.

Lewin said the type of innovation necessary for small satellites to truly make an impact would come from the commercial market. "In my mind, that's really where it's at," he added.

The search for a small satellite "killer application" is ongoing and market driven, said Jeff Ganley, Nanosat program Manager at the Air Force Research Laboratory's Space Vehicles Directorate at Kirtland Air Force Base in New Mexico.

"Big satellites, right now, the way we do it, they are hard...they are a pain. But they're the only game out there," Ganley noted. He senses that small satellites do represent a potential new technology in the aerospace industry, but with a caveat. They must be 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. It's not our focus. It's not our job. But if we ignore it, we do so at our peril," he concluded.

Tony Tether, Director of the Defense Advanced Research Projects Agency (DARPA), the central research and development organization for the U.S. Department of Defense, told those attending the small satellite meeting: "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. "We take the technological excuse off the table," he said in outlining the past achievements of his agency in pursuing innovation from the late 1950s onward.

Tether reviewed a number of past DARPA small satellite efforts, such as the Global Low Orbit Message Relay spacecraft, built in less than one year's time, launched from a space shuttle in 1985, and chalked up 14 months of successful operation.

Underscoring the need for assured use of space, Tether said that the task at hand is ensuring that the U.S. military can continue to operate as it needs to on orbit. DARPA space projects, he said, fall into five areas: Rapid, flexible space access; space-based support of real-time tactical war fighting from space; 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 towards microsatellites."

Interest in small space missions worldwide is on the increase, although the launch rate for this class satellite in the United States remains sluggish and lacking a dedicated budget, said Robert Meurer, Technical Chairman of the conference and an international sales specialist based in Leesburg, Virginia

"I think we're trying to prove utility...that's been the biggest challenge we've had," Meurer told Space News. The U.S. military's growing responsive space requirements appears to be an emerging application for small satellites, he suggested.

"That might be the nugget here...that might be the first place we really earn our stripes," according to Meurer.

Meurer said that there has been appreciable growth overseas in small satellites within the last few years, far greater than that domestically, he explained. "It is already a threat because we've seem some contracts from the United States go to foreign firms," he said.

Space situational awareness, offensive or defensive counter space, and space control in general, Meurer envisions these as probable leading roles for small satellites. A key technological driver that enables them to fulfill such duties is maneuverability. "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," Meurer said. "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."

"I think we've turned a corner," said Jan King, chief executive officer of Southern Cross Space & Communications Pty. Ltd., Weyba Downs, Queensland, Australia.

King said that three recent missions, in particular, highlight the steady progression of scientific data gathering and technology testing via small satellites: Canada's Microvariability and Oscillations of Stars microsatellite; Australia's FedSat; and NASA's Cosmic Hot Interstellar Plasma Spectrometer mission.

"Small satellites are another way of thinking about doing space. It's not just taking a big spacecraft, scale it down, and use all the same rules," King said. "You have to start from the other end. Start with nothing and figure out how you can do something from nothing."

King said that space is given too much credit for the technologies that satellites are using. The cell phone and lap top computer industries, for example, are producing micro-technologies useful for small satellites, he stated.

Those in the world space community "that don't think you can fly that stuff...they should think again," King said. "The small satellite community has shown you don't need super high-reliability parts for a short-duration mission that can do a lot of things."

As for a non-linear type of technology likely to impact small satellites in the coming years, SSTL's Sweeting looks to the Micro-Electro-Mechanical Systems -- 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 that SSTL work in earth observations is clearly disruptive to the traditional way of carrying out remote sensing tasks using far-heftier spacecraft.

Sweeting said that future SSTL work -- within the next three years -- is geared toward using Coke can-sized spacecraft that demonstrate formation flying, as well as rendezvous and docking under the watchful eye of yet another small satellite.

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."