ROCHESTER, N.Y. -- An ambitious sky survey that aims to eventually map about 10 percent of the galaxies in Earth's cosmic neighborhood is off to a remarkable start, with the Wednesday release of the most detailed and far-reaching map of the universe yet compiled.

Take a video journey through the galaxies.

The knots, which can contain thousands of galaxies, each are called clusters, and collections of those clusters form superclusters. The space between these groups can stretch as far as 200 million light-years or be broken up by strings of galaxies stretched out in long filaments. On paper, the galaxy map shows patterns that resemble the lights of cities that splatter nighttime pictures of continents taken by satellites.

The map was presented here at the meeting of the American Astronomical Society.

"Ours is the first survey to really see many hundreds of these" concentrations of clusters and filaments, said Karl Glazebrook, an astronomer at Johns Hopkins University who presented the results of the survey.

The map is unique in that it measures the galaxies not just within a square patch on the sky, but also the distances to those galaxies. The survey is designed to map one-tenth of the galaxies within 2 billion light-years of Earth. (A light-year is the distance light travels in a year -- about 6 trillion miles or 9.7 trillion kilometers).

"We like to think we've made the first large three dimensional map of the universe," Glazebrook said. "And that is 4 billion light-years deep and covers one-twentieth of the whole sky."

Glazebrook calculates the volume of the universe covered by the survey to be 13 billion billion billion cubic light-years.

"If you took every atom in the sun and replaced it with New York State, something like a couple hundred miles across, then you'd basically fill this volume," he said. The number of atoms in the sun is a 10 followed by 56 zeros.

The galaxy survey is possible thanks to an advanced robotic spectrometer installed on the 13-foot (4-meter) Anglo-Australian Telescope in New South Wales, Australia.

Called the Two-Degree Field (2dF) spectrograph, the instrument can sample an area of sky as wide as four full moons. The device can measure the characteristics of 400 galaxies at the same time, pinning down the position and distance of more than 2,000 objects each hour.

Previous surveys have measured about 25,000 galaxies, but the Two-Degree Field Survey aims to map 10 times that number by the time it is finished sometime in 2001.

The map of the universe isn't meant as a travel guide. Its usefulness lies in giving cosmologists and astrophysicists a grasp of the structure of the universe. That, in turn, helps them understand the history of the universe, how it formed and what will eventually become of it.

One of the big questions about the universe is this: Will the universe continue to expand forever, or is there enough matter in it that the gravity will eventually pull everything back together in a tremendous collapse -- the opposite of the Big Bang.

Based on the speeds of the galaxies in the Two-Degree Field Survey, team members think there is not enough mass in the universe to pull off a gigantic universal rebound. Thus, the universe will continue to expand outward forever, said Gavin Dalton an astrophysicist at the University of Oxford who built the spectrograph and analyzed the survey data.

Many more science results will come out during the coming year, Glazebrook said, as theorists closely analyze the survey data.

By the time the survey catalogs all 250,000 of its target galaxies, Dalton hopes to be well on his way to building an even more advanced instrument that can peer even further into the universe. He is working on a project to build a galaxy-survey spectrograph that can be installed on the 26-foot (8-meter) Subaru Telescope on the Mauna Kea volcano in Hawaii. That instrument will enable scientists to conduct a similar galaxy survey, but with it they will be able to search the universe at much farther distances -- beyond 2 million light-years away.

Funding for the project will come jointly from the Japanese and British governments, Dalton said. The funding from the Japanese side is set aside, and the team is waiting for the British arm of support. "We're still in the design review process, but I'd say it's about 90-percent certain that it will go ahead," he said.

"That survey will tell us about the evolution of the universe," Glazebrook said, "because it will show us what the universe was like much further back in time."