Dark energy tagged posts

Astronomers use Empty Space to study the Universe

This simulation of the large-scale structure of the universe reveals the cosmic web of galaxies and the vast, empty regions known as voids. Credit: Image by Nico Hamaus, Universitäts-Sternwarte München, courtesy of The Ohio State University

This simulation of the large-scale structure of the universe reveals the cosmic web of galaxies and the vast, empty regions known as voids. Credit: Image by Nico Hamaus, Universitäts-Sternwarte München, courtesy of The Ohio State University

A lot of information contained in cosmic voids, study suggests. An international team of astronomers reports that they were able to achieve 4X better precision in measurements of how the universe’s visible matter is clustered together by studying the empty spaces in between. Researchers looking for new ways to probe gravity and dark energy adopted a new strategy: looking at what’s not there.

Paul Sutter, Ohio State University, said that the new measurements can help bring astronomers closer to testing Einstein’s general theory of relativity, which des...

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Dark Energy measured with Record-breaking 3D Map of 1.2 million Galaxies

The Sloan Digital Sky Survey and its Baryon Oscillation Spectroscopic Survey has transformed a two-dimensional image of the sky (left panel) into a three-dimensional map spanning distances of billions of light years, shown here from two perspectives (middle and right panels). This map includes 120,000 galaxies over 10% of the survey area. The brighter regions correspond to the regions of the Universe with more galaxies and therefore more dark matter. Credit: Jeremy Tinker and SDSS-III

The Sloan Digital Sky Survey and its Baryon Oscillation Spectroscopic Survey has transformed a two-dimensional image of the sky (left panel) into a three-dimensional map spanning distances of billions of light years, shown here from two perspectives (middle and right panels). This map includes 120,000 galaxies over 10% of the survey area. The brighter regions correspond to the regions of the Universe with more galaxies and therefore more dark matter. Credit: Jeremy Tinker and SDSS-III

A team of hundreds of physicists and astronomers constructed a 3D map to make one of the most precise measurements yet of the dark energy currently driving the accelerated expansion of the Universe. “We have spent 5 years collecting measurements of 1...

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Origin of Extraordinary Supernovae can be explained by the ‘accretion scenario.’

Image around SN 2012dn obtained by the Kanata Telescope at Higashi-Hiroshima Observatory. SN 2012dn is seen near the center of this figure. The host galaxy ESO 462-G016 is seen on the left side of SN 2012dn. The distance to this galaxy is known to be 130 mega-light-years. Because the supernova is a point source, the expansion cannot be measured, but the evolutions of the brightness and color are obtained. Credit: Higashi-Hiroshima Observatory

Image around SN 2012dn obtained by the Kanata Telescope at Higashi-Hiroshima Observatory. SN 2012dn is seen near the center of this figure. The host galaxy ESO 462-G016 is seen on the left side of SN 2012dn. The distance to this galaxy is known to be 130 mega-light-years. Because the supernova is a point source, the expansion cannot be measured, but the evolutions of the brightness and color are obtained. Credit: Higashi-Hiroshima Observatory

Using Optical and Infrared Synergetic Telescopes for Education and Research (OISTER), researchers discovered an anomalously strong infrared emission from ‘the extraordinary supernova’ SN 2012dn, which has never been observed in other Type Ia supernovae to date...

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Death by Gamma-ray Bursts may place 1st Lower Bound on the Cosmological Constant

Artist's illustration of a gamma-ray burst.

Artist’s illustration of a gamma-ray burst. Energy from the explosion is beamed into two narrow, oppositely directed jets. Credit: NASA/Swift/Mary Pat Hrybyk-Keith and John Jones

Sometimes when a star collapses into a supernova, it releases gamma-ray bursts GRBs which last just a few seconds, but during that time they can release as much energy as the Sun will produce in its entire lifetime. They are so intense that, if pointed at the Earth from even the most distant edge of our galaxy, they could easily cause a mass extinction. It’s thought that a gamma-ray burst may have caused the Ordovician extinction around 440 million years ago, which wiped out 85% of all species at the time.

Clearly, the farther away a planet is from gamma-ray bursts, the better its chances of harboring advanced for...

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