Light from the first stars launches a new astronomy
After several decades of speculation, astronomers have glimpsed the shadows of the very first atoms, cast in the light of the earliest stars. Yet as significant as this discovery is, it represents only the beginning of what some scientists call "the new astronomy."
Astronomers working in this new mode will no longer scan the skies directly. Instead, they will pursue cosmic questions by searching vast databases assembled by instruments whose only goal is to garner as much information as possible about every object they can detect.
The first such database - the Sloan Digital Sky Survey - is a collaborative effort that has developed over the past 12 years among some 100 scientists at 11 institutions in Germany, Japan, and the United States. Funds from the Sloan Foundation, several US government agencies, and the collaborating institutions support it. When the survey is completed in three to four years time, instruments at Apache Point Observatory in New Mexico should have recorded the brightness, color, and shape of 100 million objects plus the distances to a million galaxies and 100,000 quasars over one-quarter of the sky.
Quasars are very compact, very bright objects that can outshine a whole galaxy of ordinary stars. One of these cosmic power houses now has produced the survey's first fruits. Survey scientist Xiaochui Fan at the Institute for Advanced Study in Princeton and several colleagues have used early survey data to locate the most distant quasar yet found. The light we now see from it left its source at the end of what astronomers call the universe's Dark Ages.