Giant Space Telescopes Possible : Orbiting Instruments Could Seek Life Beyond This Planet

Orbiting optical telescopes much larger than the biggest telescopes on Earth could permit scientists to find and examine other planetary systems in the search for life beyond this planet, a presidential commission that is drafting a blueprint for the future of the nation’s space program was told Wednesday.

Lou Allen, former Air Force chief and now director of Pasadena’s Jet Propulsion Laboratory, told the National Commission on Space meeting at JPL that putting a 400-inch telescope in orbit is “not an unreasonable thing to think about doing.”

That would be the same size as the planned Keck Telescope, which the California Institute of Technology will soon begin building atop a dormant volcano in Hawaii. And it would be more than four times the size of Space Telescope, which the National Aeronautics and Space Administration plans to have in orbit next year.

Recent breakthroughs in the design and construction of huge lenses have virtually eliminated past limitations on the practical size of telescopes, and Allen said that the nation “ought to be thinking in terms of building a 60-meter telescope (about 2,400 inches across).” If launch costs could be reduced dramatically, he suggested, it might be possible to put that one in orbit too, above the Earth’s atmosphere, which limits the effectiveness of all telescopes on the ground.

The commission, chaired by former NASA chief Thomas Paine of Brentwood, is holding a series of hearings across the country to collect thoughts from scientists about the future of the space program over the next half a century. The commission, mandated by Congress, is to submit a final report to the President next spring.

The meeting at JPL was intended to give proponents of unmanned space projects a chance to put in their bid for long-range support, since JPL is the nation’s leading center for unmanned projects.

Allen surprised some of those in the audience by suggesting that the level of funding for unmanned projects is reasonable today, although others quickly pointed out that the level has dropped to about a third of what it was a decade ago.

The present level represents a “commendable strategy,” Allen said. He suggested that more money might lead to the development of technology that would then dictate the direction that scientific research could take--a complaint heard often about the space shuttle.

“Don’t let the technology push the science,” he said, noting that scientific goals should determine the direction of technological progress, not the other way around.

Allen told the commission that discoveries in one area could dramatically alter the direction the space program will take in the years ahead. The discovery of other planetary systems, which many scientists believe is just around the corner, would reorder the nation’s priorities because of the potential significance of discovering life on other planets.

“That’s very exciting,” Allen said.

But discovery must be accompanied by the ability to study details of other planetary systems.

Another scientist addressing the commission disagreed sharply with Allen’s suggestion that the current level of funding is adequate.

The unmanned space exploration program is operating in “a highly constrained” environment because of fiscal limitations, said David Morrison, vice chancellor for research at the University of Hawaii and chairman of NASA’s Solar System Exploration Committee.