New images confirm Big Bang theory
New images capturing the "oldest light" in the universe have confirmed the Big Bang theory but revealed new mysteries that are not explained by current scientific models.
2:33PM GMT 21 Mar 2013
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The "map" of light originating from the dawn of time, captured by the £515m Planck space telescope, reveals patterns which scientists say confirm that the universe began with a Big Bang.
But it also contains subtle differences which contradict certain elements of the Standard Model of cosmology, meaning theories will have to be tweaked.
The images, released on Thursday, suggest that at 13.84 billion years the universe is older than previously thought - albeit by only 48 million years.
They also suggest it contains slightly more matter than expected and a little less "dark energy", the mysterious force which is believed to drive the expansion of the universe.
The maps were captured over 15 months by the European Space Agency telescope, by examining the faint glow of microwave radiation found in space known as the Cosmic Microwave Background (CMB).
Small ripples in the CMB represent the earliest seeds of stars and galaxies, dating back to when the universe was just 380,000 years old and consisted of a "primordial soup" of energetic particles.
The tiny variations in temperature correspond to regions which later gave rise to the structured universe we see today.
The maps appear to support the "inflation" theory, which says the universe briefly expanded faster than the speed of light an instant after the Big Bang.
"The sizes of these tiny ripples hold the key to what happened in that first trillionth of a trillionth of a second," said Planck scientist Dr Joanna Dunkley, from Oxford University.
"Planck has given us striking new evidence that indicates they were created during this incredibly fast expansion, just after the Big Bang."
Evidence from Planck also provides a better idea of how the mass-energy of the universe is divided up into parts that are visible and hidden.
Normal matter that forms stars and galaxies contributes just 4.9 per cent and dark matter, of which little is understood, makes up 26.8 per cent, a fifth more than was previously thought. Dark energy accounts for around 69 per cent.
The new age of the universe was calculated from the rate at which it is expanding outwards, which turns out to be a little slower than previous estimates.
The maps have also thrown up unexpected results due to their extremely high precision which have scientists baffled.
Over large scales the CMB fluctuations do not match those predicted by the Standard Model, the best theory of how the universe works, for example.
Opposite sides of the map appear to differ in their average temperature and one large cold spot is larger than anticipated, suggesting the universe may not be the same in all directions.
"Our ultimate goal would be to construct a new model that predicts the anomalies and links them together," said Professor George Efstathiou, another member of the team from Cambridge University.
"But these are early days. So far, we don't know whether this is possible and what type of new physics might be needed - and that's exciting."
Professor John Womersley, chief executive of the Science and Technology Facilities Council, said: "Planck has given us an amazing picture of the very earliest moments of the universe. These results are the culmination of many years of work by UK scientists and engineers supported by STFC. This kind of project can sometimes seem expensive but the pay-off in science and technology more than justifies the investment we've made."
Launched in 2009, Planck is over three times more sensitive than its predecessor, the WMAP satellite. Its high frequency microwave detector is cooled to just 0.1C above absolute zero, the coldest temperature possible.
That enables it to detect variations in the temperature of the CMB as small as a millionth of a degree.
Professor Richard Davis, who led the University of Manchester's Planck team, said: "The information extracted from Planck's new map provides excellent confirmation of the standard model of cosmology with unprecedented accuracy and sets a new benchmark for our knowledge of the ingredients of the universe.
"But because the precision of Planck's map is so high, it has also revealed some unexplained anomalies in the data that require further study. Among these interesting findings are fluctuations in the cosmic microwave background over large scales that do not match what the standard model of physics predicts, including an asymmetry in the average temperatures on opposite hemispheres of the skies."
