European Space Agency’s Planck telescope today released the most detailed map ever created of the cosmic microwave background, the relic radiation from the Big Bang.

The data also set a new value for the rate at which the Universe is expanding today, known as the Hubble constant.

At 67.15 kilometres per second per megaparsec, this is significantly less than the current standard value in astronomy. The data imply that the age of the Universe is 13.82 billion years.

The findings are based on the initial 15.5 months of data from Planck and this is mission’s first all-sky picture of the oldest light in our Universe, imprinted on the sky when it was just 380,000 years old.

At that time, the young Universe was filled with a hot dense soup of interacting protons, electrons and photons at about 2700 degrees Celsius. When the protons and electrons joined to form hydrogen atoms, the light was set free.

As the Universe has expanded, this light today has been stretched out to microwave wavelengths, equivalent to a temperature of just 2.7 degrees above absolute zero.

This ‘cosmic microwave background’ (CMB) shows tiny temperature fluctuations that correspond to regions of slightly different densities at very early times, representing the seeds of all future structure: the stars and galaxies of today.

According to the standard model of cosmology, the fluctuations arose immediately after the Big Bang and were stretched to cosmologically large scales during a brief period of accelerated expansion known as inflation.

By analysing the nature and distribution of the seeds in Planck’s CMB image, we can determine the composition and evolution of the Universe from its birth to the present day.

“The extraordinary quality of Planck’s portrait of the infant Universe allows us to peel back its layers to the very foundations, revealing that our blueprint of the cosmos is far from complete,” Jean-Jacques Dordain, ESA’s Director General said in a statement.

“With the most accurate and detailed maps of the microwave sky ever made, Planck is painting a new picture of the Universe that is pushing us to the limits of understanding current cosmological theories,” said Jan Tauber, ESA’s Planck Project Scientist.

“We see an almost perfect fit to the standard model of cosmology, but with intriguing features that force us to rethink some of our basic assumptions,” Tauber said.

One of the most surprising findings is that the fluctuations in the CMB temperatures at large angular scales do not match those predicted by the standard model – their signals are not as strong as expected from the smaller scale structure revealed by Planck.

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