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 NASA
TO "MAP" BIG BANG REMNANT TO
SOLVE UNIVERSAL MYSTERIES
The Microwave Anisotropy Probe (MAP),
scheduled for launch June 30, will journey into deep space on
a voyage to explore some of the deepest mysteries of the
cosmos.
Scientists hope to determine the
content, shape, history, and the ultimate fate of the
universe, by constructing a full-sky picture of the oldest
light. MAP is designed to capture the afterglow of the Big
Bang, which comes to us from a time well before there were any
stars, galaxies or quasars. Patterns imprinted within this
afterglow carry with them the answers to mysteries such as:
What happened during the first instant after the Big Bang? How
did the Universe evolve into the complex patterns of galaxies
that we see today? Will the Universe expand forever or will it
collapse?
To answer these questions, MAP's
measured pattern of the Big Bang's afterglow, like a
fingerprint, will be compared against the unique fingerprint
pattern predicted by each cosmic scenario to find the right
match. "We are tremendously excited about this mission
because it will help answer basic questions that people have
been asking for ages," said Dr. Charles L. Bennett,
Principal Investigator for the MAP mission at NASA's Goddard
Space Flight Center, Greenbelt, MD. "MAP's unprecedented
accuracy and precision will allow us to determine the nature
and destiny of the universe."
According to the Big Bang theory, the
universe began about 14 billion years ago as an unimaginably
hot and dense fog of light and exotic particles. The Universe
has since continuously expanded and cooled. The whole Universe
is bathed in the afterglow light from the Big Bang. The light
that is now reaching us has been traveling for about 14
billion years, thus allowing us a look back through time to
see the early Universe.
 "The
cosmic microwave light is a fossil," says Professor David
T. Wilkinson, Princeton University, Princeton, NJ. "Just
as we can study dinosaur bones and reconstruct their lives of
millions of years ago, we can probe this ancient light and
reconstruct the Universe as it was about 14 billion years
ago."
MAP views the infant universe by
measuring the tiny temperature differences within the
extraordinarily evenly dispersed microwave light, which now
averages a frigid 2.73 degrees above absolute zero
temperature. MAP will res olve
the slight temperature fluctuations, which vary by only
millionths of a degree. These temperature differences point
back to density differences in the young Universe, where
denser regions gave way to the vast web-like structure of
galaxies that we see today.
 A
great deal of effort over the past 35 years has gone into
measurements of the afterglow light from the Big Bang. In
1992, NASA's Cosmic Background Explorer satellite discovered
tiny patterns, or "anisotropy," in its full-sky
picture of the light. Balloon-borne and ground-based
experiments have further advanced our knowledge. The upcoming
MAP full-sky picture, to be made with unprecedented accuracy
and precision, will dramatically revolutionize our view of the
Universe.
MAP required an extraordinary design to achieve its accurate
and precise measurement capability. "Nothing has ever
been built like it before," said Dr. Edward Wollack, a
science team member at Goddard. "To measure the cosmic
glow reliably to a part in a million, to millionths of a
degree has been the grand challenge. That's like measuring the
weight of a cup of sand down to the resolution of a single
grain."
About a month after its launch on a
Delta II rocket from Cape Canaveral, FL, MAP will swing past
the Moon, boosting its orbit to the second Lagrange Point, or
L2. This is the first time a spacecraft will be in orbit
around the L2 point. The Italian-French mathematician Josef
Lagrange discovered five special points in the vicinity of two
orbiting masses where a third, smaller mass can orbit at a
fixed distance from the larger masses. L2 is four times
further than the Moon in the direction away from the Sun and
requires very little fuel to maintain orbit.
After a three month journey, MAP will
begin to chart the faint microwave glow from the Big Bang. It
will take about 18 months to build up a full-sky picture and
perform the analysis. The MAP hardware and software were
produced by Goddard and Princeton. Science team members are
also located at the University of Chicago, IL; the University
of California, Los Angeles; Brown University, Providence, RI;
and the University of British Columbia, Vancouver. MAP, an
Explorer mission, cost about $145 million.
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