After a number of observations and scientific articles signed by hundreds of physicists and astronomers, the first dark energy measurement was obtained, the mysterious energy that occupies 75% of the universe that makes it constantly expand.
75% of the universe that makes it constantly expand.
The measures are the result of the international project Boss (Baryon Oscillation Spectroscopic Survey), conducted as part of the SDSS-III program (Sloan Digital Sky Survey-III) and the articles are published in the journal Monthly Notices of the Royal Astronomical Society.
“We have spent five years collecting measurements of 1.2 million galaxies over one quarter of the sky to map out the structure of the Universe over a volume of 650 cubic billion light years”, says Jeremy Tinker, New York University, one of the coordinators of the research. “This map has allowed us to make the best measurements yet of the effects of dark energy in the expansion of the Universe. We are making our results and map available to the world”.
The results of this effort have been filed in recent days on arXiv.org: the map allows to make one of the most precise measurements yet of the dark energy currently driving the accelerated expansion of the Universe. The map provides important information on the dark energy, which occupies 25% of the universe and whose composition is still unknown. “We’ve made the largest map for studying the 95% of the universe that is dark”, noted David Schlegel, an astrophysicist at Lawrence Berkeley National Laboratory and principal investigator for BOSS. “In this map, we can see galaxies being gravitationally pulled towards other galaxies by dark matter. And on much larger scales, we see the effect of dark energy ripping the universe apart”. The Boss project in fact took advantage of some features of the cosmic background radiation to calculate the position of galaxies within 6 billion light years from Earth with a margin of error of 1%.
A section of the map, showing about 10% of the total. Copyright Jeremy Tinker and the SDSS-III collaboration.
These are information that allow scientists to re-examine Albert Einstein’s theory of relativity on a cosmological scale, found Shirley Ho, the Berkeley Lab and Carnegie Mellon University.
“The results from BOSS provide a solid foundation for even more precise future measurements, such as those we expect from the Dark Energy Spectroscopic Instrument (DESI)”, says Natalie Roe, Physics Division director at Berkeley. “DESI will construct a more detailed 3D map in a volume of space ten times larger to precisely characterize dark energy, and ultimately the future of our universe”.