In an office set in central New Jersey's farmland, researchers are drawing blueprints for space communities built from moon rock and powered by huge solar satellites.

It may sound like science fiction, but Gregg Maryniak says such dreams could become reality at the start of the next century."We're trying to change from thinking of space as a void to thinking of it as a font of energy and material resources that makes it a good place for people," says Maryniak, executive vice president of the Space Studies Institute.

Maryniak and Gerard K. O'Neill, a nuclear physicist and professor emeritus at Princeton University who founded the institute in 1977, are among those driven by the belief that man is rapidly consuming the Earth's natural resources and making it uninhabitable with pollution and garbage.

They believe new energy sources could be developed in space.

"I see this kind of activity as one of the few bright rays of hope in a situation that otherwise appears to be hopeless," Maryniak said in an interview at the institute, which is housed at a former rocket engine plant.

Since it's too expensive to carry materials into space, scientists must develop construction materials that are already available there, he said. The closest source is the moon.

The private, non-profit institute already has developed three prototypes of a "mass driver" - a machine used to launch baseball-size fragments of mined moon rock to a central collection place in space. Maryniak describes the collection spot as a "celestial catcher's mitt."

He says moon rock, composed mainly of oxygen, silicon and metals, can be broken into building materials and fuel using solar energy.

The latest mass driver is a tube 11/2-feet wide and 500 feet long that propels material into space at a rate of 11/2 miles per second.

The moon rock could be used to build solar power satellites that would collect sunlight, convert it to electricity and beam it to earth.

Such satellites, up to 5 miles long and 11/2 miles wide, could produce as much electricity as three or four nuclear reactors and provide all the energy needs of a city the size of New York or Chicago, Maryniak says.

Totally self-sufficient space cities could be built with agricultural areas, controlled atmosphere, water supplies and gravitational field. Such cities would house tens of thousands of people and have trees, rivers and birds.