...HOW I WONDER WHERE YOU ARE
By 1995, American astronomers plan to begin the most
ambitious stellar
map-making project ever: They'll chart the cosmic distribution of a
million
galaxies and 100,000 quasars, pinpointing their locations on a three-dimensional
relief map that stretches to the edge of the universe.
``That's nearly a hundred times
larger than any stellar catalog that's ever
existed before,'' says Princeton University's
Jeremiah P. Ostriker.
The Sloan Digital Sky Survey--named after the Alfred P. Sloan
Foundation, which
is providing $8 million of the project's $25 million cost--is due to wrap
up by
the turn of the century. The collected data should not only resolve some ancient
debates
about how structures like clusters and superclusters of galaxies arose,
but also make all
previous stellar maps obsolete.
The key to the groundbreaking sky survey lies in a new
telescope still under
construction. When completed, it will be installed at Apache Point,
New Mexico,
near the Sacramento Park Observatory. The telescope's primary mirror, 2.5
meters
in diameter, boasts four times the light-collecting power of the one used 40
years
ago in the Palomar Sky Survey. And 30 charge-coupled-device light
detectors enable the
telescope to capture more of the light collected by the
mirror--an impressive 60 percent of
the photons that reach it. The images seen
with the telescope will be produced directly in
digital form, ready for
immediate classifying and cataloging, Ostriker says.
In addition to
charting the distribution of stellar matter, the sky survey
should also shed new light on
dark matter and may uncover new kinds of objects
never before seen.