The NASA/ESA Hubble Space Telescope has offered once more a series of astonishing images of 250 ultra-faint dwarf galaxies noticed in distant clusters MACS0717, MACS0416 and Abell 2744.
The deepest images ever captured with gravitational lensing have revealed the 250 earliest and faintest galaxies until now. Their discovery is indeed astonishing and couldn’t have been performed without the extraordinary capabilities of the NASA/ESA Hubble Space Telescope. Using observational data retrieved from the deep imaging telescope, the international team of researchers, led by Ecole Polytechnique Fédérale de Lausanne’s, Doctor Hakim Atek initially studied the images of the three distant galaxy clusters.
These images were captured and are credited to the Hubble Frontier Fields program. Spanning three years and including 840 orbits, the program aims to collect as much data as possible on six distant galaxy clusters that may reveal more on the origin and formation of the universe.
The astonishing images of 250 ultra-faint dwarf galaxies revealed a trove of information to the astronomers team. Most of these very distant galaxies are born only 600 million years following the Big Bang. The light emitted from the stars took 12 billion years to reach the NASA/ESA Hubble Space Telescope. Their faint light is particularly the point of interest for astronomers.
Doctor John Richards with the Observatoire de Lyon, France, who was involved in the study, stated:
“The faintest galaxies detected in these Hubble observation are fainter than any other yet uncovered in the deepest Hubble observations”.
Not only are they ultra-faint, but astronomers now believe that the accumulated light of such galaxies are crucial for the Epoch of Reionization. A coined scientific term for the period of time when the gas in the universe transformed from being neutral to being fully ionized. The hydrogen gas present in the early Universe was dispersed through the process of reionization.
As a result, UV light was able to travel larger distances without the foggy cloak blocking the way. The Universe became what astronomers call transparent to UV light. And it is galaxies like the 250 ultra-faint dwarf galaxies unraveled by the NASA/ESA Hubble Space Telescope that play a major role in maintaining the universe as such.
Doctor Atek explained that light emitted by massive galaxies and thus brighter is not sufficient to reionize the universe. The faintest and most distant galaxies are a key actor in the process.
The images are found on the website of the Hubble Space Telescope. The study is pending publishing in the Astrophysical Journal.