Planck satellite: Maps detail Universe's ancient light

A map tracing the "oldest light" in the sky has been produced by Europe's Planck Surveyor satellite. Its pattern confirms the Big Bang theory for the origin of the Universe but subtle, unexpected details will require scientists to adjust some of their ideas.

Map of the oldest light in the Universe.

The map shows tiny deviations from the average background temperature, where blue is slightly cooler and red is slightly warmer. The cold spots are where matter was more concentrated and later collapsed under gravity to form stars and galaxies. Image: ESA/Planck Collaboration


Related Stories

A spectacular new map of the "oldest light" in the sky has just been released by the European Space Agency.

Scientists say its mottled pattern is an exquisite confirmation of our Big-Bang model for the origin and evolution of the Universe.

But there are features in the picture, they add, that are unexpected and will require ideas to be refined.

The map was assembled from 15 months' worth of data acquired by the 600m-euro (£515m) Planck space telescope.

It details what is known as the cosmic microwave background, or CMB - a faint glow of long wavelength radiation that pervades all of space.

Its precise configuration, visible in the new Planck data, is suggestive of a cosmos that is slightly older than previously thought - one that came into existence 13.82 billion years ago.

This is an increase of about 50 million years on earlier calculations.

The map's pattern also indicates a subtle adjustment is needed to the Universe's inventory of contents.

It seems there is slightly more matter out there (31.7%) and slightly less "dark energy" (68.3%), the mysterious component thought to be driving the cosmos apart at an accelerating rate.

"I would imagine for [most people] it might look like a dirty rugby ball or a piece of modern art," said Cambridge University's George Efstathiou, presenting the new picture here at Esa headquarters in Paris.

"But I can assure you there are cosmologists who would have hacked our computers or maybe even given up their children to get hold of this map, we're so excited by it."

Planck is the third western satellite to study the CMB. The two previous efforts - COBE and WMAP - were led by the US space agency (Nasa). The Soviets also had an experiment in space in the 1980s that they called Relikt-1.

How Planck's view hints at new physics

Planck anomalies graphic
  • The CMB's temperature fluctuations are put through a number of statistical analyses
  • Deviations can be studied as a function of their size on the sky - their angular scale
  • When compared to best-fit Big Bang models, some anomalies are evident
  • One shows the fluctuations on the biggest scales to be weaker than expected
  • Theorists will need to adjust their ideas to account for these features

The CMB is the light that was finally allowed to spread out across space once the Universe had cooled sufficiently to permit the formation of hydrogen atoms - about 380,000 years into the life of the cosmos.

It still bathes the Earth in a near-uniform glow at microwave frequencies, and has a temperature profile that is just 2.7 degrees above absolute zero.

But it is possible to detect minute deviations in this signal, and these fluctuations - seen as mottling in the map - are understood to reflect the differences in the density of matter when the light parted company and set out on its journey all those years ago.

The fluctuations can be thought of as the seeds for all the structure that later developed in the cosmos - all the stars and galaxies.

Scientists subject the temperature deviations to a range of statistical analyses, which can then be matched against theoretical expectations.

This allows them to rule in some models to explain the origin and evolution of the cosmos, while ruling out a host of others.

The team that has done this for Planck's data says the map is an elegant fit for the standard model of cosmology - the idea that the Universe started in a hot, dense state in an incredibly small space, and then expanded and cooled.

At a fundamental level, it also supports an "add-on" to this Big Bang theory known as inflation, which postulates that in the very first moments of its existence the Universe opened up in an exponential manner - faster than light itself.

But because Planck's map is so much more detailed than anything previously obtained, it is also possible to see some anomalies in it.

Temperature anomalies in Planck data Planck has confirmed the north/south differences and a "cold spot" in the data

One is the finding that the temperature fluctuations, when viewed across the biggest scales, do not match those predicted by the standard model. Their signal is a bit weaker than expected.

Planck's new numbers

  • 4.9% normal matter - atoms, the stuff from which we are all made
  • 26.8% dark matter - the unseen material holding galaxies together
  • 68.3% dark energy - the mysterious component accelerating cosmic expansion
  • The number for dark energy is lower than previously estimated
  • The new age - 13.82 billion years - results from a slower expansion
  • This is described by a value known as the Hubble Constant
  • It too is revised to 67.15 km per second, per megaparsec (3.2 million light-years)

There appears also to be an asymmetry in the average temperatures across the sky; the southern hemisphere is slightly warmer than the north.

A third anomaly is a cold spot in the map, centred on the constellation Eridanus, which is much bigger than would be predicted.

These features have been hinted at before by Planck's most recent predecessor - Nasa's WMAP satellite - but are now seen with greater clarity and their significance cemented.

A consequence will be the binning of many ideas for how inflation propagated, as the process was first introduced in the 1980s as a way to iron out such phenomena.

The fact that these delicate features are real will force theorists to finesse their inflationary solutions and possibly even lead them to some novel physics on the way.

"Inflation doesn't predict that it should leave behind any kind of history or remnant, and yet that's what we see," Planck project scientist Dr Jan Tauber told BBC News.

CMB - The 'oldest light' in the Universe

Detail of CMB data
  • Theory says 380,000 years after the Big Bang, matter and light "decoupled"
  • Matter went on to form stars and galaxies; the light spread out and cooled
  • The light - the CMB - now washes over the Earth at microwave frequencies
  • Tiny deviations from this average glow appear as mottling in the map (above)
  • These fluctuations reflect density differences in the early distribution of matter
  • Their pattern betrays the age, shape and contents of the Universe, and more and follow me on Twitter: @BBCAmos


More on This Story

Related Stories

The BBC is not responsible for the content of external Internet sites


This entry is now closed for comments

Jump to comments pagination
  • rate this

    Comment number 251.

    Originally (by science) the sun / solar system was dated based on heat output of coal - hence this 6000 years figure.
    This before the understanding of atomic fusion.
    How can 6000 years be correct?

  • rate this

    Comment number 250.

    Something, can come from nothing, contrary to what most people imagine this concept to be.


  • rate this

    Comment number 249.

    @192 - Let's be honest, even Christians argue over their own interpretation of the same book, just as scientists argue over interpretation of the data of an experiment.

  • rate this

    Comment number 248.

    *Sigh* - another science vs religion debate... it becomes more and more about 'prejudice' rather than a pursuit of 'truth'

    Stunning image, especially the asymmetry of 'hot' and 'cold' spots... Interested to see how this ties in with the tentatively confirmed Higgs Boson and potential Higgs Field.

    P.s. Any notion of 'God' should exist in ALL things - not just the blinkered views of one.

  • rate this

    Comment number 247.

    @222. middle
    People lose faith that the most dangerous thing ? alot wil be thinking what's the point in life ???

    I don't have faith and never have. I have always been very positive about the world and interested in learning as much as possible whilst I'm alive. I intend to simply enjoy experiencing life's adventures and social interactions until it ends. I have no concerns about afterlife/soul.

  • rate this

    Comment number 246.

    I love this kind of story, it's interesting.

    But what I hate is the ability to comment on them and you get on the posters about bible/creation and anti-bible nonsense.

    Please BBC stop with the allowing comments on science pages. Let us just enjoy the discovery in our own way without having to read the nonsense.

  • rate this

    Comment number 245.

    All these religious people claiming "Science is rubbish" on an internet forum...

  • rate this

    Comment number 244.

    "Do people who dismiss religion also dismiss spirituality in general?"

    Spirituality and science don't have to be in conflict. For example the Dali Lama is a big fan of progression and science, and many scientists have spiritual opinions and beliefs.

    The conflict lays with dogma, intolerance and Canon: Spirituality codified in dusty, unswerving tomes which demands blind denial or ignoring of fact

  • rate this

    Comment number 243.

    Amazing news and a big congratulations to all people that participated in this discovery!

    Knowing where it is we come from only helps us more in working out where we are going. Real progress has been made and I hope this discovery is given more media attention.

  • rate this

    Comment number 242.

    @Jabdi, you're missing the point. Scientists aren't so arrogant to assume they know the facts. As znz said, they try their hardest to disprove everything. The fact that we lived beyond 5 has nothing to do with it. That laptops work isn't proof that we know stuff. It means we understand it as much as we presently can - that's not fact, it's a best guess scenario which hasn't been disproved yet.

  • rate this

    Comment number 241.

    Anyone who believes in big bang/chance plus standard evolution needs to realise this means they are simply a bag of meaningless chemicals and free will is an illusion. When you 'die' you cease to be and therefore anything you do is worthless! In reality atoms of carbon and hydrogen do not care about you.

  • rate this

    Comment number 240.

    Great to see that this is the top story on the beeb at the moment.

    If only educationalists could tap into this interest and motivate more young people to study the sciences, maths and engineering.

  • rate this

    Comment number 239.

    "To any people commenting that the Bible says the earth is 6000 years "old, it does not. The Bible supports the big bang, in actual fact."

    THANK YOU another sane person on here! The bang theory provides an explanation for the physical nature of the universe, God being the spiritual cause. the bible and science are inline. this is the teaching of the Catholic church the only church to teach this.

  • rate this

    Comment number 238.

    My 8 year old loves science. Some of the questions he has asked are typical of children I guess: Why is the cosmos believed to have started with a Big Bang? What CAUSED the Big Bang? What was BEFORE the Big Bang?

    I told him we don't know, it's a theory and God only knows the answer. Quick as a flash or big bang he said, but what came before God? I nearly wet myself!!

  • rate this

    Comment number 237.

    @226 A_From_Oxford: If you really were a physicist you would not be willing to accept propositions like "god" without some sort of evidence or rational justification. "God" is just a baseless, meaningless concept which means different things to everyone who uses the word. It is an answer for nothing.

  • rate this

    Comment number 236.

    196, David, the things you list, dark matter dark energy etc, must have come from somewhere. We've taken the bricks down to a Higgs Bosun, but it might as well be the size of a house brick. Science is clear, nothing comes from nothing, unless there's a proper answer, no matter how small the bricks get, to what went bang, why did it go bang, and where did it come from?

  • rate this

    Comment number 235.

    The Big Bang anomalies are not consistent, and hence reject the Big Bang which does not (a) allow for large scale structure in the Cosmic Microwave background (b) does not allow for an asymmetry in the average temperatures in the southern hemisphere.

    What you seem to be saying is that if we fudge the theory again, then we could make the data CONSISTENT with the Big Bang (it does not CONFIRM it)

  • rate this

    Comment number 234.

    @226 A_from_Oxford I'm being a bit off topic here, but you might be interested to read "A History of God" by Karen Armstrong, which looks at how the Bible came together from different sources into one volume, and how the elements that remain - like two different accounts in Genesis - reflect the ideals, goals and personal beliefs of the authors. A fasconating read - for Christian or Atheist alike.

  • rate this

    Comment number 233.

    @220 nelch

    I like to think of 2,476,633 as an inflated figure - seems to me that the god mentioned in the bible took a bit of pride in his mass slaughter of innocents. He's bound to have bragged that figure up a bit to his mates down the pub.

  • rate this

    Comment number 232.

    48. Edward
    Just looks like a lot of dots to me.. Haven't we got better things to do?

    Nice one, Edward. If everyone in history had had your attitude, we'd still be living in mud huts and dying of starvation due to tooth decay in our early thirties. Luckily though, each generation has had some people with more positive outlooks, and perhaps more natural intelligence, than you.


Page 11 of 23


More Science & Environment stories



BBC © 2014 The BBC is not responsible for the content of external sites. Read more.

This page is best viewed in an up-to-date web browser with style sheets (CSS) enabled. While you will be able to view the content of this page in your current browser, you will not be able to get the full visual experience. Please consider upgrading your browser software or enabling style sheets (CSS) if you are able to do so.