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Planck's most detailed map ever reveals an almost perfect Universe - 0 views

  • the most detailed map ever created of the cosmic microwave background
  • the relic radiation from the Big Bang
  • was released
  • ...31 more annotations...
  • revealing the existence of features that challenge the foundations of our current understanding of the Universe
  • The image is based on the initial 15.5 months of data from Planck and is the 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 2700ºC
  • 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.
  • 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.
  • Planck was designed to map these fluctuations across the whole sky with greater resolution and sensitivity than ever before
  • 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
  • because precision of Planck's map is so high, it also made it possible to reveal some peculiar unexplained features that may well require new physics to be understood
  • Since the release of Planck's first all-sky image in 2010, we have been carefully extracting and analysing all of the foreground emissions that lie between us and the Universe's first light
  • revealing the cosmic microwave background in the greatest detail yet
  • 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
  • Another is an asymmetry in the average temperatures on opposite hemispheres of the sky
  • This runs counter to the prediction made by the standard model that the Universe should be broadly similar in any direction we look
  • a cold spot extends over a patch of sky that is much larger than expected.
  • The asymmetry and the cold spot had already been hinted at with Planck's predecessor
  • NASA's WMAP mission, but were largely ignored because of lingering doubts about their cosmic origin
  • One way to explain the anomalies is to propose that the Universe is in fact not the same in all directions on a larger scale than we can observe
  • In this scenario, the light rays from the CMB may have taken a more complicated route through the Universe than previously understood, resulting in some of the unusual patterns observed today.
  • ultimate goal would be to construct a new model that predicts the anomalies and links them together
  • we don't know whether this is possible and what type of new physics might be needed
  • the Planck data conform spectacularly well to the expectations of a rather simple model of the Universe, allowing scientists to extract the most refined values yet for its ingredients
  • dark energy, a mysterious force thought to be responsible for accelerating the expansion of the Universe, accounts for less than previously thought.
  • Normal matter that makes up stars and galaxies contributes just 4.9% of the mass/energy density of the Universe
  • Dark matter, which has thus far only been detected indirectly by its gravitational influence, makes up 26.8%, nearly a fifth more than the previous estimate.
  • Planck 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.
  • 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
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Planck's Cosmic Map Reveals Universe Older, Expanding More Slowly - 0 views

  • show the same 10-square-degree patch of sky as seen by NASA’s Cosmic Background Explorer, or COBE, NASA’s Wilkinson Microwave Anisotropy Probe, or WMAP, and Planck.
  • Planck has a resolution about 2.5 times greater than WMAP
  • This graphic
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Universe is a teeny bit older than thought | Matter & Energy | Science News - 0 views

  • Launched by the European Space Agency in 2009, the Planck satellite scans the sky for the cosmic microwave background, radiation that dates back to about 380,000 years after the Big Bang
  • Planck is essentially a supersensitive thermometer that can probe the temperature of this radiation to millionths of a degree
  • The red spots in the map are about 1 part in 100,000 hotter than the average temperature, while the blue spots are slightly colder
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  • the theory of inflation, which posits that, around 10-30 seconds after the Big Bang, the universe briefly expanded faster than the speed of light.
  • Researchers who analyzed the telescope’s data announced that the universe is about 13.81 billion years old, or 80 million years older than previously thought
  • The telescope is still making observations, and in about a year researchers will add
  • data t
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