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Astronomers have used NASA / ESA's Hubble Space Telescope and ESA's Gaia Space Observatory to perform the most accurate measurements of the rate of expansion of the Universe since its calculation there is nearly a century. The results, published in the Astrophysical Journal provide further evidence of the gap between the rate of expansion of the Near Universe and that of the distant early Universe. This "tension" implies that there could be a new physics underlying the foundations of the Universe; the possibilities include the force of interaction of dark matter, the black energy being even more exotic than previously thought, or a new unknown particle in the tapestry of space [19659002]. The most accurate measurements to date of the rate of expansion of the Universe. This is calculated by measuring distances between nearby galaxies using special types of stars called cepheid variables as cosmic bounds. By comparing their intrinsic luminosity as measured by Hubble, with their apparent luminosity seen from Earth, scientists can calculate their distances. Gaia further refines this measurement by geometrically measuring distances to Cepheid variables in the Milky Way. This allowed astronomers to more precisely calibrate the distances to Cepheids that are seen in outer galaxies. Photo Credit: NASA / ESA / A. Field, STScI ” src=”http://cdn.sci-news.com/images/2018/07/image_6205-Hubble-Constant.jpg” width=”580″ height=”605″/>
Using NASA / ESA Hubble and ESA's Gaia Spatial Telescopes, Riess et al performed the most accurate measurements the rate of expansion of the Universe. This is calculated by measuring distances between nearby galaxies using special types of stars called cepheid variables as cosmic bounds. By comparing their intrinsic luminosity as measured by Hubble, with their apparent luminosity seen from Earth, scientists can calculate their distances. Gaia further refines this measurement by geometrically measuring distances to Cepheid variables in the Milky Way. This allowed astronomers to more precisely calibrate the distances to Cepheids that are seen in outer galaxies. Photo Credit: NASA / ESA / A. Field, STScI
"The tension seems to have become a total incompatibility between our visions of the early and late Universe," said Professor Adam Riess, of the Space Telescope. Science Institute and Johns Hopkins University
"At this point, it is clear that this is not just a gross mistake in any given measure.It is as if you had predicted how much a child would grow up of a growth chart and then you discover that the adult that he has outgrown has far exceeded the prediction.We are very perplexed. "
In 2005, Professor Riess and members of the Supernova H0 team for the State Equation (SHOES) set out to measure the rate of expansion of the Universe with unprecedented accuracy.
By refining their techniques, researchers have reduced the uncertainty of the rate measurement to unprecedented levels
Now, with the combined power of Hubble and Gaia, they have reduced this uncertainty to only 2.2%. [19659005] They measured the current rate of expansion This means that for every 3.3 million farther away, a galaxy belongs to us, it seems to move 45.6 miles per second faster.
The results of another space observatory, ESA's Planck mission, predict that the Universe is expected to expand today to just 67 km / s per megaparsec
"Planck mapped the early Universe as it appeared only 360,000 years after the Big Bang," astronomers said.
"The whole sky is printed with the signature of the microwave encoded Big Bang." Planck measured the sizes of the ripples in this cosmic microwave background (CMB) that were produced by slight irregularities in the ball The small details of these ripples encode the amount of dark matter and normal matter, the trajectory of the Universe at that time and other cosmological parameters. "
These measurements, again under evaluation, allow scientists to predict the beginning of the Universe. probably would have evolved towards the rate of expansion that we can measure today. However, these predictions do not seem to correspond to the new measurements of our near contemporary Universe.
"With the addition of these new Hubble and Gaia data, we now have a serious voltage with the CMB data," said a member of the Planck team. Dr. George Efstathiou, of the Kavli Institute for Cosmology, who was not involved in the new work
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Adam G. Riess et al . 2018. Cepheid standards of the Milky Way to measure cosmic distances and application to Gaia DR2: Implications for the Hubble constant. ApJ 861, 126; doi: 10.3847 / 1538-4357 / aac82e
