A team of astronomers has discovered the most distant galaxy ... - 20minutos.es

Galaxy Image class=”text”> z8-GND-5296, the most distant ever discovered, as it was 700 million years after the Big Bang. (V.TILVI, SL Finkelstein, C. Papovich, STSCI / NAS)

A team of astronomers has discovered the most distant galaxy ever known .

The galaxy, called 8-GND-5296, you see how was just 700 million years after the Big Bang , when the universe was only 5% of its current age of 13,800 million of years, concludes the investigation of these experts, published in Thursday’s edition of the journal Nature .

class=”imp”> The galaxies we see how it was just 700 million years after the Big Bang, when the universe was only 5% of its current age With the collaboration of experts University of Texas at Austin, University of Texas A & M and the National Optical Astronomy Observatories in the United States, astronomers at the University of California, Riverside, United States, Bahram Mobasher and Naveen Reddy identified a galaxy far distant using deep optical and infrared images taken by the Hubble Space Telescope . Follow-up observations with the Keck Telescope in Hawaii confirmed their distance.

In their search for distant galaxies, the team selected several candidates, depending on their colors , of the nearly 100,000 galaxies identified in the Hubble Space Telescope images taken as part of the survey CANDELS , the largest project undertaken by the telescope, with a total time allocated for around 900 hours.

However, use colors to classify galaxies is difficult because some objects nearby may be masked as distant galaxies.

redshift, measuring distances in the universe

To measure the distance to galaxies in a definitive way, used spectroscopy, ie the amount of the wavelength of light from a galaxy has shifted toward the red end of the spectrum as he travels from galaxy to Earth, due to the expansion of the universe, a phenomenon called ‘redshift’. Since the expansion velocity and the distances of galaxies are proportional, the redshift gives astronomers measure the distance to galaxies.

class=”imp”> When you look at distant objects, we see them as they were in the past “What makes this unique galaxy, compared with other discoveries of this type, is the Spectroscopic confirmation distance “said Mobasher, Professor of Physics and Astronomy Observational.

astronomer explained that because light travels at about 186,000 miles per second, when we look at distant objects, see them as they were in the past . The more distant we take these observations, we can see farther in the past.

“By observing a galaxy far back in time, we can study the first galaxies form,” he said. “By comparing the properties of galaxies at different distances, it is possible to explore the evolution of galaxies throughout the universe’s age,” said Mobasher.

MOSFIRE, a revolutionary instrument

The discovery was made possible by a new instrument, MOSFIRE in the Keck Telescope , a highly sensitive tool that is designed to detect infrared light, a region of the spectrum where the length shifts wave of light emitted from distant galaxies, and could point to several objects at once.

MOSFIRE class=”imp”> in the Keck Telescope, is an extremely sensitive tool that is designed to detect infrared light This last feature was what allowed researchers to observe 43 galaxies candidates in only two nights with Keck observations and obtain higher quality than previous analyzes.

Of the 43 galaxies observed with MOSFIRE, a single galaxy, z8-GND-5296, highlighted with a redshift of 7.5 .

observations showed that it is forming stars very rapidly, with an annual production of approximately 300 times the mass of our Sun , while the Milky Way form only two or three stars per year.

new distance record holder is in the same part of the sky than the previous record holder (a redshift of 7.2), which also happens to have a very high rate of star formation.