Hubble and Einstein credited for the discovery of ancient galaxies

For the first time, Scientists were able to observe a distant galaxy which was formed in the early days of the Universe, just 500 million years after the Big Bang. The discovery was possible thanks to the Hubble Space Telescope and the general relativity theory of Albert Einstein

The oldest picture of the universe have been acquired by scientists using electromagnetic noise left from the Big Bang, a kind of diffuse halo that can not be associated with any star, galaxy or other astronomical object. 

This occurs in less than 400,000 years after the Big Bang, a period that can be compared to a fraction of a second, according to the age of the universe (13.7 billion years). No star existed at that time, only the hydrogen atoms that were just created. It took another billion years to have another detailed image, but the landscape was already radically changed: the Universe was containing galaxies that included billions of stars.  

What has happened in the meantime?

Astronomers find it difficult to answer, because they can not separate the cosmological background noise from the signals that come from the far corners of space. Wei Zheng from Department of Physics and Astronomy of the Johns Hopkins University in the U.S., and colleagues have formed an initial answer to this question, revealing a galaxy that formed approximately 500 million years after the Big Bang. They turned their attention to Albert Einstein's theory, according to which very massive objects have a gravitational field so strong that they manage to deflect the light rays passing near them. And sometimes, this deformation has the effect of enhancing the perceived image of an observer located on the other side of the field. Such a phenomenon is called "gravitational lens".

Scientists have used Hubble telescope to search for distant galaxies, hidden behind massive clusters of galaxies, which could serve as "magnifying glass". After analyzing 12 "clusters" of galaxies, they have discovered a distant galaxy, formed 500 million years after the Big Bang, according to the study published Wednesday in the Nature, a British journal.

Building huge terrestrial telescopes should lead to new discoveries like this, allowing scientists to explore new fields of the Universe.