The astounding discovery was made by international researchers at Harvard-Smithsonian Center for Astrophysics and Durham University in the UK.
The astronomers touted the unprecedented discovery as “hugely exciting” and likened it to finding the remains of the very first human on Earth.
The research suggests galaxies Segue-1, Bootes I, Tucana II and Ursa Major I are some of the first star clusters ever formed.
These distance and ancient galaxies are faint spots of light orbiting our very own Milky Way galaxy.
If true, the galaxies would be more than 13 billion-years-old each.
The findings were published in The Astrophysical Journal by Carlos Frenk, Durham, in collaboration with Dr Sownak Bose at Harvard Dr Alis Deason at Durham.
Dr Frenk said: “Finding some of the very first galaxies that formed in our universe orbiting in the Milky Way’s own backyard is the astronomical equivalent of finding the remains of the first humans that inhabited the Earth. It is hugely exciting.”
Scientists believe some of the very first basic atoms began forming when the cosmos was only 380,000-years-old.
These were atoms of hydrogen – the least complex of all the elements on the periodic table.
According to the CERN Institute in Switzerland, home to the Large Hadron Collider (LHC), the first moments after the universe came into existence were extremely hot and dense.
With time, as the universe cooled down, the building blocks of matter dubbed quarks and electrons pooled together to produce protons and neutrons.
Hundreds of thousands of years later the first atoms of hydrogen began to form, followed soon after by atoms of helium.
More than 1.6 million years later, the gravity from the monstrous clouds of hydrogen and helium began to form the very first stars and galaxies.
Further into the process and heavier elements such as carbon and iron began to form in the hearts of the stars and were be released into space during supernova eruptions.
The researchers have now identified two sets of satellite galaxies dated back to those very early days of the universe.
One set of galaxies is believed to have formed in the “cosmic dark ages” when the universe spent about 100 million years to cool down after the Big Bang.
The second group of galaxies was likely formed hundreds of millions of years later when ionised hydrogen cooled into so-called dark matter halos.
Dr Sownak said: “A nice aspect of this work is that it highlights the complementarity between the predictions of a theoretical model and real data.
“A decade ago, the faintest galaxies in the vicinity of the Milky Way would have gone under the radar.
“With the increasing sensitivity of present and future galaxy censuses, a whole new trove of the tiniest galaxies has come into the light, allowing us to test theoretical models in new regimes.”
Dr Deason added even the tiniest of dwarf galaxies can answer many of the mysteries of the universe.