A new astronomical study has located what appears to be the oldest building blocks of the Milky Way galaxy, which could be upwards of 13 billion years old.
According to researchers, these objects must have formed at least one hundred million years after the Big Bang and, probably, contain some of the first starts that ever shed light in our galaxy.
Now, it is important to remember, of course, that our Milky Way galaxy is only one of the billions of other galaxies in the entire Universe. And each of these several billion galaxies represents a cosmic neighborhood of hundreds of planets and billions of stars that were all formed when these smaller building blocks—like these galaxies—collided and merged.
The research team consists of scientists from the Durham University Institute for Computational Cosmology as well as the Harvard-Smithsonian Center for Astrophysics, and they found this faintest evidence of satellite galaxies that are orbiting our very own Milky Way galaxy to conclude that these are among the oldest—perhaps the very first to form—in our Universe.
Of course, scientists working in this field describe the findings as “hugely exciting,” noting that it may be “equivalent to finding the remains of the first humans that inhabited the Earth.”
Effectively, the research describes that when the universe was roughly 380,000 years old, the first atoms formed. These, of course, were hydrogen atoms, and they collected into clouds and began to cool to gradually form small “halos” of dark matter, following the Big Bang. This cooling phase—known as the “Cosmic dark ages” lasted roughly 100 million years. The gas eventually cooled within the halos and became unstable; and that is what formed the first stars.
According to Durham University’s Professor Carlos Frenk, who is the Director of Institute for Computational Cosmology: “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.”
He goes on to say, “Our finding supports the current model for the evolution of our Universe, the ‘Lambda-cold-dark-matter model’ in which the elementary particles that make up the dark matter drive cosmic evolution.”
The finds of this study have been published in the Astrophysical Journal.