March 20, 2013
J.D. Harrington
Headquarters, Washington
202-358-5241
j.d.harrington@nasa.gov
Whitney Clavin
Jet Propulsion Laboratory, Pasadena, Calif.
818-354-4673
whitney.clavin@jpl.nasa.gov
RELEASE: 13-079
PLANCK MISSION BRINGS UNIVERSE INTO SHARP FOCUS
WASHINGTON -- The Planck space mission has released the most accurate
and detailed map ever made of the oldest light in the universe,
revealing new information about its age, contents and origins.
Planck is a European Space Agency mission. NASA contributed
mission-enabling technology for both of Planck's science instruments,
and U.S., European and Canadian scientists work together to analyze
the Planck data.
The map results suggest the universe is expanding more slowly than
scientists thought, and is 13.8 billion years old, 100 million years
older than previous estimates. The data also show there is less dark
energy and more matter, both normal and dark matter, in the universe
than previously known. Dark matter is an invisible substance that
only can be seen through the effects of its gravity, while dark
energy is pushing our universe apart. The nature of both remains
mysterious.
"Astronomers worldwide have been on the edge of their seats waiting
for this map," said Joan Centrella, Planck program scientist at NASA
Headquarters in Washington. "These measurements are profoundly
important to many areas of science, as well as future space missions.
We are so pleased to have worked with the European Space Agency on
such a historic endeavor."
The map, based on the mission's first 15.5 months of all-sky
observations, reveals tiny temperature fluctuations in the cosmic
microwave background, ancient light that has traveled for billions of
years from the very early universe to reach us. The patterns of light
represent the seeds of galaxies and clusters of galaxies we see
around us today.
"As that ancient light travels to us, matter acts like an obstacle
course getting in its way and changing the patterns slightly," said
Charles Lawrence, the U.S. project scientist for Planck at NASA's Jet
Propulsion Laboratory (JPL) in Pasadena, Calif. "The Planck map
reveals not only the very young universe, but also matter, including
dark matter, everywhere in the universe."
The age, contents and other fundamental traits of our universe are
described in a simple model developed by scientists, called the
standard model of cosmology. These new data have allowed scientists
to test and improve the accuracy of this model with the greatest
precision yet. At the same time, some curious features are observed
that don't quite fit with the simple picture. For example, the model
assumes the sky is the same everywhere, but the light patterns are
asymmetrical on two halves of the sky, and there is a cold spot
extending over a patch of sky that is larger than expected.
"On one hand, we have a simple model that fits our observations
extremely well, but on the other hand, we see some strange features
which force us to rethink some of our basic assumptions," said Jan
Tauber, the European Space Agency's Planck project scientist based in
the Netherlands. "This is the beginning of a new journey and we
expect our continued analysis of Planck data will help shed light on
this conundrum."
The findings also test theories describing inflation, a dramatic
expansion of the universe that occurred immediately after its birth.
In far less time than it takes to blink an eye, the universe blew up
by 100 trillion trillion times in size. The new map, by showing that
matter seems to be distributed randomly, suggests that random
processes were at play in the very early universe on minute "quantum"
scales. This allows scientists to rule out many complex inflation
theories in favor of simple ones.
"Patterns over huge patches of sky tell us about what was happening on
the tiniest of scales in the moments just after our universe was
born," Lawrence said.
Planck launched in 2009 and has been scanning the skies ever since,
mapping the cosmic microwave background, the afterglow of the
theorized big bang that created our universe. This relic radiation
provides scientists with a snapshot of the universe 370,000 years
after the big bang. Light existed before this time, but it was locked
in a hot plasma similar to a candle flame, which later cooled and set
the light free.
The cosmic microwave background is remarkably uniform over the entire
sky, but tiny variations reveal the imprints of sound waves triggered
by quantum fluctuations in the universe just moments after it was
born. These imprints, appearing as splotches in the Planck map, are
the seeds from which matter grew, forming stars and galaxies. Prior
balloon-based and space missions learned a great deal by studying
these patterns, including NASA's Wilkinson Microwave Anisotropy Probe
(WMAP) and the Cosmic Background Explorer (COBE), which earned the
2006 Nobel Prize in Physics.
Planck is the successor to these satellites, covering a wider range of
light frequencies with improved sensitivity and resolution. Its
measurements reveal light patterns as small as one-twelfth of a
degree on the sky.
"Planck is like the Ferrari of cosmic microwave background missions,"
said Krzysztof Gorski, a U.S Planck scientist at JPL. "You fine tune
the technology to get more precise results. For a car, that can mean
an increase in speed and winning races. For Planck, it results in
giving astronomers a treasure trove of spectacular data, and bringing
forth a deeper understanding of the properties and history of the
universe."
The newly estimated expansion rate of the universe, known as Hubble's
constant, is 67.15 plus or minus 1.2 kilometers/second/megaparsec. A
megaparsec is roughly 3 million light-years. This is less than prior
estimates derived from space telescopes, such as NASA's Spitzer and
Hubble, using a different technique. The new estimate of dark matter
content in the universe is 26.8 percent, up from 24 percent, while
dark energy falls to 68.3 percent, down from 71.4 percent. Normal
matter now is 4.9 percent, up from 4.6 percent.
Complete results from Planck, which still is scanning the skies, will
be released in 2014.
NASA's Planck Project Office is based at JPL.
For more information about Planck, visit:
http://www.nasa.gov/planck
and
http://www.esa.int/Our_Activities/Space_Science/Planck
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