BALTIMORE -- These galaxies are long ago and far away, thousands of them, the earliest and most distant ever photographed.

They're the galaxies of the Hubble Ultra Deep Field -- the first fruits of a continuing project at the Space Telescope Science Institute in Baltimore. Eventually, astronomers expect to capture the glow of tens of thousands of them. And they are all waiting in what looks like an "empty" spot of sky just one-tenth of the diameter of the moon.

"The field itself is just beautiful, just rich with different things," said Steven V.W. Beckwith, director of the institute. He gathered a half-dozen Ultra Deep Field astronomers around his computer screen last week for their first glimpse of the project's results -- some of the earliest galaxies to form after the Big Bang.

They glowed on the monitor in a bewildering variety of shapes and colors -- neat pinwheels and messy blobs of silver and gold, thin, steely streaks and intense points of light as red as rubies. "Think of the universe today as a 50-year-old person," Beckwith said. "The changes in people in their early formative years are much faster (than in later life). This is also true of the universe."

The Ultra Deep Field observations will allow astronomers to peer backward to a time when the "50-year-old" universe was closer to 2 or 3. "We're really beginning to probe the universe in its infancy at this stage," Beckwith said. Looking back is possible in astronomy because the more distant an object is, the longer it has taken for the light we see to reach Earth. So we see these objects as they appeared millions or billions of years ago.

Beckwith compared the Ultra Deep Field project to the deep sediment cores drilled by geologists studying the Earth's history. The deepest layers in the core will reveal things about the environment hundreds or thousands of years ago. As they move higher on the core, they can identify changes in that environment, and in the life forms that lived in it.

The Ultra Deep Field provides a similar "core," revealing objects along a continuum of time, from the relatively nearby and "recent" to the extremely distant and earliest objects. Analysis of the light from each object will reveal how long ago the light left it, and how distant it is.

To see to that far, Hubble scientists needed to target a region of the sky relatively free of the space dust that might block the faint light of distant galaxies. It also had to be empty of bright, nearby stars and galaxies that would wash out the view. They also wanted a spot that could be seen from key ground-based observatories in both the northern and southern hemispheres, and one with good "guide stars" to help Hubble find its target. "There weren't very many options, a handful," said astronomer and project coordinator Massimo Stiavelli.

Gathering light from so far away demands patience. The photons have traveled for billions of years, and they straggle, one by one, into the detectors in Hubble's Advanced Camera for Surveys. As more photons arrive, more objects become visible, and visible objects begin to reveal more shape and detail.

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