By taking advantage of gravitational lensing, observations by the NASA/ESA Hubble Space Telescope have revealed the biggest sample of the faintest and earliest known galaxies in the universe. The formation of some of the discovered galaxies took place just 600 million years after the Big Bang. They are fainter in comparison to any other galaxy Hubble has discovered so far.

It is for the first time that the team has confidently determined that these small galaxies have played an important role in the creation of the beautiful universe that we witness today.

An international group of researchers, headed by Hakim Atek of the Ecole Polytechnique Fdrale de Lausanne, Switzerland, has found more than 250 small galaxies that came into existence just 600-900 million years after the Big Bang. These are among the biggest samples of dwarf galaxies that have not been found at these epochs.

These galaxies’ light took more than 12 billion years in reaching the telescope that permitted the astronomers to look back in time when the universe was still quite young.

The breakthrough is quite impressive. However, the number of galaxies discovered at this early epoch was not the only remarkable breakthrough of the team. Johan Richard from the Observatoire de Lyon, France, pointed out, “The faintest galaxies detected in these Hubble observations are fainter than any other yet uncovered in the deepest Hubble observations”.

The team observed the light coming from the galaxies, and came to know that the accumulated light emitted by these galaxies may have played a vital role in one of the most mysterious periods of early history of the universe, the epoch of reionization.