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Physics + MathPhysics & Math

Image of the Early Universe Is Only 4.9 Percent Regular Matter

ByTim De ChantNOVA NextNOVA Next

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In an unfinished Italian palace, surrounded by frescoes that dried some 600 years ago, astronomers revealed their latest piece—a portrait of the universe when it was just 380,000 years old, as captured by the Planck spacecraft.

And what a work of art it is. Microwave ripples—their peaks just 0.000075 K hotter than their troughs—texturize the colorful signatures of heat released from galactic dust. It’s in this earliest image that astronomers see the universe for what it was 13.8 billion years ago—a suffocatingly hot place dominated by the dark energy that’s fueling its expansion.

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Ripples of microwave radiation texturize the heat emissions of galactic dust.

Also lurking in the image are regular matter (just 4.9% of what we see) and dark matter (26.6 %). Yet despite those statistics, the Planck team still has no answer to just what dark matter and dark energy are. Here’s Dennis Overbye, reporting for the New York Times:

Planck dealt a blow to another possible dark matter candidate, namely a brand of the ghostly particles known as neutrinos. Physicists have known of three types of neutrinos for some time and have wondered if there were any more, whose accumulated mass would affect the evolution of the universe. Planck’s results leave little room for a fourth kind, so-called sterile neutrinos.

Though we may not be any closer to discovering what makes up the majority of the universe, astronomers are inching closer to finding the B-mode swirls that would prove the inflationary theory of the universe. Though the BICEP2 team failed in their latest attempt to tease out those polarized microwaves, they have partnered with the Planck team, which has access to a larger number of frequencies. Their combined data set has the potential to be that much more explanatory, and their mutual analysis will be revealed this January. It’s certain to shed even more light on the earliest days of the universe.

Image credit: Planck/ESA