Astronomers believe a newly discovered cluster of stars is proof that a dark matter-dominated galaxy is hiding nearby

Feb 9, 2015 10:27 GMT  ·  By

Astronomer Sukanya Chakrabarti with the Rochester Institute of Technology in the US and fellow researchers believe to have found evidence that a small galaxy drowning in dark matter is lurking not far from our cosmic home, the Milky Way.

In a report in the Astrophysical Journal Letters, the specialists explain that, all things considered, chances are that the reason this dwarf galaxy has not yet been documented by science is that it is hiding behind a whole lot of clouds made up of dust and gas.

Zooming in on this unknown dwarf galaxy

Rochester Institute of Technology scientist Sukanya Chakrabarti and colleagues say that, for the time being, the only evidence indicating the presence of a dark matter-dominated dwarf galaxy not far from our Milky Way is a group of juvenile, pulsating stars.

As detailed in the Astrophysical Journal Letters, these stars sit at a distance of about 300,000 light-years from us in the direction of the Norma constellation in the southern hemisphere. Being so far from us, the stars cannot be part of the Milky Way.

Instead, astronomers suspect that they mark the location of a dwarf galaxy that is yet to be discovered and that packs a whole lot of dark matter. Whether this prediction is spot on remains to be seen.

“These young stars are likely the signature of this predicted galaxy,” argues Chakrabarti, assistant professor at the Institute's School of Physics and Astronomy. “They can’t be part of our galaxy because the disk of the Milky Way terminates at 48,000 light years,” she adds.

OK, so what's the deal with this dark matter?

The reason dark matter is called, well, dark matter is that it cannot be studied directly with the help of telescopes or whatever other complicated gadgets and gizmos we humans have put together since we first discovered the wonders of technology.

As explained by scientists, dark matter neither emits nor absorbs light. Hence, its properties and even its existence can only be inferred from its effects on the appearance and the evolution of the universe.

Thus, astronomers say that it is only by taking into account the gravitational pull of this so-called dark matter that the movement of various objects through the cosmos can be fully explained.

In fact, the gravitational pull of dark matter is so great that, having measured it, scientists concluded that dark matter could account for as much as 80% of the known cosmos. However, brainiacs are yet to figure out all the right ingredients that go into making dark matter.