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The universe according to Planck

Sharper image of early cosmic radiation released

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TURIN, Italy — A sharper view of the early universe than any other image has captured so far was released July 5 by the European Space Agency. Its Planck satellite, launched in May 2009, has been sweeping the sky to record microwave radiation, the remnant glow from the Big Bang, which created the universe about 13.7 billion years ago.

Planck’s new image, recorded at nine frequencies, depicts subtle variations in the universe’s temperature at different points in the sky, reflecting the distribution of matter when the universe was 380,000 years old. At that time the initial cosmic fireball receded, allowing radiation to flow freely through space. Patterns within the cosmic microwaves provide clues to the history of the universe, including the formation of galaxies and their growth into huge structures. Planck data will also help pin down even more precisely various properties of the cosmos, such as how old it is and what mix of various forms of matter and energy it is made of.

In the Planck map, the white and blue areas represent foreground interference from the Milky Way and other galaxies; that data must be subtracted before the primordial microwaves (represented by the yellow and reddish portions of the image) can be fully analyzed. Do not attempt to analyze the visible portion of the primordial microwaves on your own, though. This image has been intentionally degraded to prevent scientists not on the Planck team from drawing any premature conclusions, Nazzareno Mandolesi, the principal investigator for one of Planck’s instruments, said during a news conference in Turin at the ESOF 2010 conference, organized by the Euroscience Open Forum.

Positioned at a gravitationally stable point 1.5 million kilometers from Earth, the Planck satellite should ultimately improve measurements of basic cosmological data by a factor of five compared with NASA’s WMAP satellite, which was launched in 2003 and has provided the most precise microwave background information available so far.

Planck’s new map was based on six months of sky sweeps. ESA plans to release findings on some matters of astrophysical interest by early next year, Mandolesi said, but results on major cosmic questions are not planned for public release until 2012.

Further Reading

ESA News Release: [Go to]

Planck mission home page: [Go to]

ESOF 2010 [Go to]

R. Cowen. Planck by Planck. Science News. Vol. 175, April 11, 2009, p. 16. Available online: [Go to]

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