Planck: Best Map Yet of Cosmic Creation

Planck mission scientists have released the first half of the spacecraft's observations of the cosmic microwave background.

On March 21st, scientists with the European Space Agency's Planck mission announced their long-anticipated results from the spacecraft’s first 15.5 months of mapping the cosmic microwave background.

The CMB is the radiation released about 380,000 years after the Big Bang, when the newborn universe cooled down enough to become transparent and let light travel free. We see this light today redshifted to microwave wavelengths, and slight temperature variations across its wallpaper-like "surface" reveal how matter was distributed at that early era. These variations allow cosmologists to test theories of what was happening in the universe in the tiniest instants after its birth, including the momentous but brief period of inflation.

Planck's data of cosmic power spectrum
The strength of temperature variations (vertical) is plotted against their angular sizes (horizontal). The green line was predicted by current cosmic-origins theory; the red dots are Planck data.
Planck Collaboration
Planck’s superbly precise new picture of the CMB (below) shows remarkable agreement with theoretical work, confirming that observations fit a simple cosmological model defined by just six numbers. (Take that in for a moment: the whole physical universe is described by six numbers. Even your phone number takes 10 digits in the U.S.)

The graph at right might not mean much to the average Joe, but it shows how much temperatures fluctuate in patches of various angular sizes all across the sky. Our inflationary model makes specific predictions about what this complex graph should look like. As you can see, Planck’s observations (red dots) trace nigh perfectly the theory (green line). My colleague Alan freaked out when he saw the tight fit at the graph's far right — you don’t appreciate the wonders of scientific progress until you have a 6-foot-3 man jumping up and down in your office.

But Planck also introduces a few surprises that need explaining.

By the Numbers

Planck launched on May 14, 2009, as successor to NASA’s phenomenal Wilkinson Microwave Anisotropy Probe (WMAP), which mapped the CMB for nine years. WMAP observed in five frequency bands spanning 22 to 90 GHz, and its results form the bedrock of modern cosmology — helping nail down values such as the age of the universe (13.77 billion years) and how much of the matter in the universe is “dark” (about 84%) when combined with other measurements.

Planck’s more precise numbers are slightly different from WMAP’s. Planck covered nine bands from 30 to 857 GHz, and it’s still working in the three lowest bands. The sweet spot for observing the CMB — where the galaxy’s dusty, star-studded plane is the least bothersome — is from 70 to 150 GHz, making Planck an ideal follow-up to WMAP, Planck team member Bruce Partridge (Haverford College) said last month in Boston at the annual meeting of the American Association for the Advancement of Science.

Planck cosmic microwave background
The oldest light in our universe, seen today as the cosmic microwave background, suffuses the cosmos. This all-sky map, created from all nine frequency bands of the Planck spacecraft, shows the CMB's details at a precision never before acquired. Click for high resolution (5.5 MB). See comparison with WMAP.
ESA and the Planck Collaboration
When combined with other types of measurements, the Planck data homes in on an age for the universe of 13.798 billion years, give or take a mere 0.037. And it pushes down what fraction of everything in the universe is dark energy, from 71.4% to 69.2%.

(These numbers may be slightly different from what you see reported elsewhere: the numbers are all consistent, it just depends what other information is added to the CMB data.)

One of the most notable new numbers is the value for the Hubble constant. The Hubble parameter, the ratio of a galaxy’s recession velocity (redshift) to its distance, describes the rate at which the universe is expanding. Its value has changed over time; the present value is called the Hubble constant. Looking farther into the universe — earlier in time — measures a past value, explains Adam Riess (Johns Hopkins University), who shared the 2011 Nobel Prize in Physics for discovering that the universe’s expansion is accelerating.

“There is always some extrapolation, since by definition we can’t measure anything at exactly now,” he says. “It’s always the past.”

Astronomers use various tactics to estimate the Hubble constant. In the “local” universe, meaning within tens to hundreds of millions of light-years, they use standard candles such as exploding white dwarfs or Cepheid variable stars. One candle promoted by researchers at Villanova University (my alma mater — Go ’Nova!) and also used by another team in a recent Nature paper is eclipsing binary stars, which allow observers to determine stars’ real luminosity based on exact measurements of the stars’ diameters and temperatures derived from their eclipses.

The current value for the Hubble constant based on local standard candles is 73.8 +/- 2.4 km/s per megaparsec. (All uncertainties quoted here are at the 68% confidence level.) That's slightly in tension with the value extrapolated from WMAP data. The CMB-based value depends on what other data are included and the cosmological model used; the value announced with WMAP’s final 9-year results last December is 69.32 +/- 0.80. Astronomers have been waiting to see whether Planck would uphold this tension, because if the discrepancy is real it could imply something unexpected is afoot in physics.

Planck delivered. The Hubble constant derived from Planck’s first 15.5 months of CMB observations (combined with other measurements) is 67.80 +/- 0.77.

“I think this is one of the most exciting parts of the data that came out,” says Planck scientist Martin White (University of California, Berkeley, and Lawrence Berkeley National Lab). The fact that astronomers starting at opposite ends of cosmic history and moving toward the middle aren’t getting quite the same value for this parameter is going to attract a lot of attention, he says. It could signal a problem with the models or funky new physics — or even that the amount of dark energy somehow increases with time in a given volume of space. “That’s a pretty radical thing to propose, and so this is not something that we should take lightly,” he cautions.

A Boatload, In Brief

Planck’s results will be far-reaching — the project's scientists released more than two dozen papers today, and other researchers have already started downloading the raw data to work with. Some other noteworthy results in today’s announcement are:

  • No extra neutrinos. According to the Standard Model, there should be three and only three flavors of neutrinos, nearly massless particles speeding through the universe at ultrarelativistic speeds. Planck upholds that expectation.
  • The universe isn’t as uniform on the largest scales as expected. Previous work had hinted that the northern and southern hemispheres of the sky don’t look as much like each other (statistically speaking) as they should, and that there’s an anomalous cool spot in the CMB. (Anomalous in terms of shape, not temperature or overall size). Planck upholds these results. Furthermore, you get slightly different values for the fundamental six parameters when you fit each half of the sky separately. Assuming these effects are real, they may hint at unpredicted structure that's larger than our cosmic horizon and originating before inflation, even before the Big Bang.
  • Similarly, the wiggly power spectrum graph (shown above) may have some problems over large patches of the sky. While the agreement between observation and theory is extraordinary at small angular scales, temperature fluctuations in the CMB at the largest scales don’t behave as well. The team can’t maneuver the graph to fit these points without losing the beautiful fit elsewhere.
  • When inflation ended in the infant universe (about 10-35 second after the Big Bang, 10 nano-nano-nano-nanosecond), microscopic quantum fluctuations were slightly stronger on larger scales than smaller ones. These fluctuations served as the seeds of today's large-scale cosmic structure. Simple inflation predicts what this slight "tilt” of the fluctuations' size distribution should be. WMAP found this tilt, but Planck confirms its value to high accuracy. Score a big win for standard inflation.
  • No polarization announcement yet. The real test of inflation, which cosmologists eagerly await, should come from specific polarization patterns in the CMB created by gravitational waves. Other theories of what caused the Big Bang, such as colliding "branes" in higher-dimensional space, predict that there will be no such polarization patterns. Looking for them was a prime reason why Planck was built. Mission scientists said that those polarization data are not cleaned up enough yet to be usable; we'll have to await analysis of a longer span of Planck's data. The next release of results is planned for 2014.

If you’d like the dirty details, you can find all the Planck papers online. The summary of results is in Section 9 of Paper I.

The European Space Agency has put up many excellent graphics and explanations. Start here and see the sidebar on the right.

26 thoughts on “Planck: Best Map Yet of Cosmic Creation

  1. Roland Dechesne

    "The CMB is the radiation released about 380,000 years ago"

    Actually, the author likely meant, the CMB is the radiation released about 380,000 years after the Big Bang.

    RASC Calgary

  2. Robert L. Oldershaw

    One possible explanation for the newly verified dipole anisotropy in the CMB is that the structure of the cosmos has a fractal geometry and nature’s hierarchy extends far beyond the observable universe.

    Unlike the radical idea of a multiverse of 10^500 different universes with random properties, the discrete fractal paradigm proposes one unified physics for the entire cosmos. It is a new paradigm that is based on enlarging the symmetry properties of nature, rather than invoking ad hoc and thoroughly untestable speculations.

    Robert L. Oldershaw
    Discrete Scale Relativity/Fractal Cosmology

  3. Robert L. Oldershaw

    Imagine a “Maxwell Demon” of infinitesimal size deep in the interior of a type-II supernova event.

    Surveying his observable environment of about 10^-18 cubic centimeters, he draws the following conclusions.

    1. There is global expansion, as he can see from the velocities of the 10^11 gigantic particles.

    2. Superimposed upon this global expansion there are random velocities of about 700 km/sec that he calls “peculiar velocities” and indicate some unexplained very high-energy and chaotic phenomena.

    3. The unusual "weblike" filamentary/void distribution of the particles reminds him of high energy plasma phenomena.

    4. The overall distribution of the gigantic particles looks very homogeneous, at least statistically speaking, but there is a small dipole anisotropy, i.e., slightly more particles and slightly higher temperatures in one direction and slightly lower values in the opposite direction.

    We then move “Maxwell” by about 10^15 centimeters to a location far outside of the supernova event. With mouth and eyes wide open, he utters two 4-letter words. The first is “Holy” and the second begins with “S”.

    Robert L. Oldershaw
    Discrete Scale Relativity/Fractal Cosmology

  4. Peter WilsonPeter Wilson

    The graph with the “nigh perfect” fit is a mathematical function, like a power law, that is physically generic. That is why, as Oldershaw points out, a supernova explosion seen from the inside would look the same.

  5. Peter WilsonPeter Wilson

    “…confirming that observations fit a simple cosmological model defined by just six numbers.” The sixth number being lambda (dark energy), nature unknown. As I’ve pointed out before, this model is TOO simple; it’s missing two parameters, distance-between-clumps, R, and energy coupling, (the Greek letter) eta. Mainstream cosmologists are in complete denial that anything is missing from their six-parameter model, dismissing as “coincidence” the fact that eta/R^2 has the same dimensions–per square meter–as lambda. The theoretical reasons why we should expect eta to be divided by R^2 in the solution are beyond the scope of the comments section. Suffice it to say, I don’t trust the six-number model when I can count seven!

  6. Pete Jackson

    Your map and text don’t explain the context of ‘northern’ and ‘southern’. Presumably, you mean in galactic coordinates since virtually all CMB maps are rendered in galactic coordinates, not least because the Milky Way and its associated microwave emissions that need to be subtracted from these maps, runs along the equator in these maps. While considered a given for readers familiar with this subject, it may not be immediately apparent for many S & T readers.

    The deviation of the amplitude of the temperature variations from the predictions, at the lowest multipole number 2 (the quadrupole) has been known since the days of COBE (1992) which made the first all-sky CMB maps at large angular scales. Whether it says something significant about isotropy at the largest angular scales, or whether we happen to just be in a ‘local’ part of the universe that has a large random deviation from the mean has been long debated/speculated.

  7. Danielle

    As a person that enjoys reading about the heavens and marvels at the universe when I look up into the heavens at night, I wondered for years about the Creation or Evolution philosophies. I have enjoyed the Hubble telescope images that display some incredible photos.

    My curiosity led me to Bible studies. It was hard for me to believe that a giraffe and an ant came from some cell oozing around in water. The complexity of the human eye and the fact that man has been able to see for thousands of years sold me on a Creator.

    Just finishing up a great quarter in our Bible study guides which can be found online here:

    One other issue is that Mt. St. Helens is a treasure trove for the scientist. We can see how layer upon layer of sediment formed in just a few hours after the explosion occurred back in May 1980.

    Carbon 14 radiometric dating is not a perfect way to date any living thing as there is far more carbon in the atmosphere now thanks to man and human progress.

    It is easier for me to believe the Biblical flood story and that our earth is around 6,000 or so years old. Believing that the earth is billions of years old is not based on scientific fact.

    There are some things that man just cannot comprehend about the Creator God. “‘The secret things belong unto the Lord our God; but those things which are revealed belong unto us and to our children forever.’ [Deuteronomy 29:29.] Just how God accomplished the work of creation he has never revealed to men; human science cannot search out the secrets of the Most High.

  8. Anthony BarreiroAnthony Barreiro

    Thank you for this clear and contextualized report. When I heard on the BBC world service and NPR that ESA had reported Planck findings that the universe is older than previously believed, I knew I could wait for Sky and Telescope to explain these findings in depth but at a level I would be able to understand.

    [paragraph break]P.S. to Danielle — I also believe that we humans will never completely understand the creation of the universe. But there is great value in trying, and we have made a lot of progress over the centuries. These empirical data about the state of the universe 380,000 years after the mysterious big bang 3.8 billion years ago are quite an accomplishment!

  9. RodRod

    If Planck finds no evidence of this, does this mean there is no inflation epoch? If we have no inflation epoch, what happens to the horizon problem? This is a light-travel-time problem in explaining the smoothness of the CMBR.

  10. James Grose

    Not to be rude, but this is NOT the place to be spreading religious mythology, yeah I said it, religious mythology. Come on, this is the 21st century, not the medieval period. Granted you have your right to believe in your religious mythology, but for the sake of everyone else, KEEP IT OUT of this discussion, there is NO room for religious debate in what is supposed to be a scientific discussion. Go troll somewhere else. The bible is nothing more than a collection of fables that have been translated and re-translated through out history, and things have a way of being changed through subsequent translations, and that is all I am going to say about this, and drop it. A piece of advice, try thinking for yourself for once, instead of letting a book of fables do it for you, you just may find out that your life would be alot more fun and rewarding.

  11. RodRod

    James, I see you feel strongly that the Bible is a book of fables. Yes S&T is not the website to discuss this topic. Perhaps you should try ICR, AiG, or CMI sites. There is much posted there to show if the Bible is fables or contains real history and not just garbled text transmission. I hope you realize that your position may be just as religious as Danielle.

  12. Al

    Interesting article & no doubt really exciting discoveries for all involved. Six numbers? A little more work should refine that down to just one number… it’s forty-two… 😉

  13. Bruce Mayfield

    Danielle, I share your appreciation for the both the Bible as God’s word and the universe as the work of God’s hands. The physical heavens really do “declare the glory of God” and I’m happy to be living in a time when humans are able to see this as never before with the help of giant telescopes and satellites like Hubble and Planck. It is sad that the wide acceptance of evolutionary biology has lead science to seek answers that leave out the possibility of there even being a Creator. Yes, we learn about God primarily from his word, but we can also learn things about his great wisdom and power by means of what astronomers and other scientists have discovered. For example, some of astronomy’s greatest discoveries are that universe is mind bogglingly huge, the fact that it is expanding, and now the fact that the rate of universal expansion found to be accelerating! These are fantastic discoveries that reveal the staggering power of the One who brought it all into being.

  14. Bruce

    Yesterday before seeing your comment Danielle I found just some of the numerous verses in the Bible that speak of God’s “stretching out the heavens.” (Job 9:8, Psalms 104:2, Isaiah 40:22, 42:5, 44:25, 45:12, Jeremiah 10:12 and Zechariah 12:1) These verses include the idea of both past and current, continuing action. Cosmologists call the force driving the acceleration of universal expansion “dark energy”. They call it dark because it’s not understood yet. I think that without the inclusion of an entity outside our realm of observation this force will never be accurately understood, but that line of thinking is not presently allowed in scientific debate (See James Grose’s comment). One of the title’s of God in the Bible is “the Ancient of Days” (Daniel 7:13) A scientific finding that His production (the universe) is 13.8 billion years old does nothing to diminish God’s everlastingness. I think the universe looks old because it is old. The same can be said for the earth and our solar system being 4.6 or so billion years old. An Entity with no beginning would not view time the same way we do. (See Psalms 90:4 and 2 Peter 3:8)

  15. Peter WilsonPeter

    The Bible contains useful material. For example, it is written, “Behold, I give you ever herb bearing seed.” And Jesus taught, “Nothing a man puts in his mouth can defile him. Only what comes out of a man’s mouth can defile him.” If we took these passages seriously, we would not be “at war” with the many God-given herbs that men put in their mouths. On the other hand, the Bible is not useful as an astronomy textbook. Why would God put things in the Bible that man can discover on his own? What is important? That we pay attention to what Jesus taught? Or that we insist, “It happened exactly like that”? Anyway, the Biblical passage most relevant to the subject at hand is the first. “In the beginning, God created the heavens and Earth.” Science has come a long way in filling in the details of this broad brush-stroke, but as for finding a first-cause, other than God, science has not even left the starting gate.

  16. RodRod

    Danielle, Bruce, Peter, et al. Some interesting posts on this report. I think we need to look at how cosmology views the origin of the universe too. In science these folks are invoking another scalar field different than the Higgs scalar field or boson to cause the big bang in inflation theory (a scalar field that is not confirmed by testing). So the 1st cause is not God but a quantum energy fluctuation in an area <= Planck length. Our universe (because there are many others according to cosmology) evolves naturally via random particle collisions giving rise to life on earth over billions of years. Today cosmology has a 1st cause in inflation theory so many claim God is not needed to create anything. My personal opinion – such a 1st cause in science is just as religious as people who accept Genesis 1:1 as proclaiming the 1st Cause.

  17. Bruce

    Excellent points Rod. Consider in detail what he is saying: The Planck length is in principle the shortest measurable length possible in nature, about 10E-20 times the diameter of a proton. Cosmologist are asking us to put faith (believe) in the notion that our for all practical purposes infinite universe arose accidentally from a random quantum fluctuation. Yes indeed Rod, it would take faith to believe in something like that. I’d rather base my beliefs on something more concrete.

  18. Robert L. Oldershaw

    For centuries many have assumed that the observable universe (u) was essentially equivalent to the whole Universe (U).

    A minority of natural philosophers, notably Spinoza and
    Kant, have strenuously countered that the u = U assumption is very dubious, is empirically unmotivated, and indicates a regrettable anthropocentric bias.

    They argued that if one used the observable universe as a
    guide for modeling the Universe, then an infinite hierarchical model was a much more scientific assumption.

    Since neither Spinoza nor Kant knew that stars were
    hierarchically organized into vast "island universes" called
    galaxies, the discovery of galaxies in the 20th century was an impressive vindication of their hierarchical paradigm.

    Why do many still assume that u = U? Well, perhaps those who
    do not learn the lessons of history are condemned to repeat past mistakes.

    Robert L. Oldershaw
    Discrete Scale Relativity/Fractal Cosmology

  19. vincenzo

    This is all very well and Planck is a nice experiment, but knowing the amount of dark energy to within 1% brings us no closer to knowing what it actually is.

  20. Howard

    Planck has confirmed the very significant anomaly in the low order multipoles of the CMB spectrum. These must be explained before the LCDM model can be fully confirmed. Now some of the cosmologists are suggesting they may be due to an asymmetric "big crunch" prior to the Big Bang. But the anomalies may actually originate closer to home as distortions caused by the geometry of the plasma heliosheath that surrounds our solar system. For further information see this brief link and the links contained therein:

  21. Bruce

    Thinking outside the box WILL likely be required to crack this riddle, but will ideas from outside the box even be given a fair hearing? Oldershaw is right to point out that history does tend to repeat itself. “Powers that be” in any age often stifle ideas that are “outside the box” of current belief. In Galileo’s day advancement away from an earth centered universe was hindered by a Church hierarchy that was married to obsolete ideas that weren’t even based on what the Bible truly says. Today there is an academic/scientific hierarchy that attempts to stifle any discussion of intelligent design as an alternative explanation for our existence. But fortunately, the truth does eventually come out.

  22. Peter WilsonPeter

    It’s a scientist’s job to be skeptical. Reportedly, geophysicists did not believe in rogue waves for the longest time. They studied the wave-equation, and concluded that rogue waves were a mathematical impossibility. They believed rogue waves were sailors‘ drunken exaggerations, or excuses used by sea captains to explain the careless loss of a ship…until three geophysicists got hit by a rogue wave. Their research vessel sank, but they lived to tell the story. I believe God is like a rogue wave: a mathematical impossibility, but being hit by One will make you a believer.

  23. Bruce

    That’s an apt analogy Peter. Of course, rouge waves aren’t really impossible are they? They merely seemed to be impossible to some due to an incomplete understanding. One of the reasons I believe the Bible is that it contains fulfilled prophecies. But accurately foretelling the future is humanly impossible. If (and I use "if" for the benefit of unbelievers) the as yet unfulfilled prophecies come true then disbelief in God will become an impossibility.

  24. Russ

    ‘Creation’ ? I thought this was a science magazine. Also don’t want to see the universe referred to as ‘the heavens’. Ah, I just can’t see reading this mag anymore. No more renewals… bye.

  25. Bruce

    Russ, you don’t comment very often, but when you have I’ve enjoyed your historical perspectives. As a student of history you know that beliefs come and go. Currently religion in general is in very ill repute among the well informed, and rightly so, due to the many abuses committed. Now science has laid out a theory that proposes an explanation for existence that omits any need for God, and this has gained wide acceptance. But the fact that many believe something doesn’t make it actually correct. From your comment it’s easy to tell that you must not be too fond of some of my comments. I don’t begrudge you of the right to your opinions, which you are as free to state as anyone. So you’re offended by the use of certain words like “creation” and “the heavens.” I guess you were mad at NASA for naming one of the Hubble images “The Pillars of Creation.” You seem to be attempting to punish S&T for the actions of some of its readers. But people of faith also buy astronomy magazines, telescopes, books, etc. Thanks for reminding me that I need to renew my subscription.

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