The most significant finding from the new data was that there are early galaxies that are “much more different” than the ones we’re familiar with such as the Milky Way.
The oldest and farthest known galaxy in the universe may have just been detected.
A team of researchers that has spent years searching for the earliest objects in the universe now reports the detection of what may be the most distant galaxy ever found. Adi Zitrin, a NASA Hubble Postdoctoral Scholar in Astronomy, and Richard Ellis, a professor of astrophysics at University College, London, have described evidence for a galaxy called EGS8p7 that is more than 13.2 billion years old.
The method enabled the astronomers to parse out signals from the noise in Hubble’s images, providing the first estimate of the number of primordial galaxies in the early Universe.
What the scientists were able to do was use all of the available data to create “one mosaic image of the sky”, and then they removed all of the stars and galaxies.
In essence, the scientists were taking a look back in time to the “epoch of reionization”, a few hundred million years after the Big Bang, Mitchell-Wynne said.
Second, EGS8p7 has a visible Lyman-alpha line, a signature of hydrogen gas heated by ultraviolet radiation pouring out of stars in their infancy.
Mitchell-Wynne and co-authors looked at data spanning optical and infrared wavelengths. This shouldn’t have been possible at the galaxy’s redshift-measured at 8.68-because typically such radiation is absorbed.
“We believe it’s true that there is intrahalo light, but we made a new discovery by looking at five infrared bands with Hubble”, he said. “We type of overlap with CIBER after which go into quick optical wavelengths, and we see along with intrahalo mild a brand new element – stars and galaxies that fashioned first within the universe”, mentioned UCI cosmologist Asantha Cooray.
The CIBER analysis suggested there would be intrahalo light in the infrared bands, but the researchers were still not entirely sure what to expect in the optical ones.
In this latest study, the researchers focused on the pixels between galaxies and stars.
“We can separate noise from the faint signal associated with first galaxies by looking at the variations in the intensity from one pixel to another”. We do not see that signal in the optical [wavelengths], only in infrared. “This is confirmation that the signal is from early times in the Universe”. The primordial galaxies in all probability housed a better variety of large stars.
Henry C. Ferguson, an astronomer at Baltimore’s Area Telescope Science Institute and co-principal investigator for CANDELS stated, “It is a very thrilling discovering”.