A Entire Galaxy Found To Be Made Entirely Of 999 Percent Dark Matter


Astronomers are saying that they’ve discovered a galaxy which is entirely made of 999 percent dark matter.

The 999 percent dark matter figure, is to many, about as confusing as trying to figure out what dark matter is, even when it’s already confused with dark energy.

The Inquisitr wrote about the latest research by astrophysicists who found out just how elusive dark matter is, which is explained in the article.

In the context of this recent discovery, another article by Scientific American explains how the Dragonfly Telephoto Array in New Mexico, initially detected the dark matter filled galaxy in February of 2015.

Three-dimensional distribution of dark matter in the Universe (artist’s impression).
[Image by NASA, ESA and R. Massey/California Institute of Technology/Hubble Space telescope | Public Domain]
It also refers to a report about the initial discovery of the galaxy by Space.com, but it should be noted that the array is designed to look for objects that aren’t bright enough to see with other telescopes.

A galaxy called Dragonfly 44 was discovered in those scans which they found was emitting 1 percent of the light from a group of 1,000 galaxies in what is referred to as the Coma Cluster, still the brightest despite it.

The way they were able to determine that it was 999 percent dark matter, was when they noticed that the galaxy — despite that it had very few stars — was holding itself together, not by the gravity of a celestial object, but the gravity from the empty space which they concluded was dark matter; otherwise the stars would drift apart and be pulled by other gravitational forces nearby.

The W. M. Keck Observatory in Hawaii where astronomers come to study the stars. [Image via Niksnut | Flickr | Cropped and resized | CC BY-SA 2.0]
Pieter van Dokkum of Yale University and his colleagues were the ones who made the initial discovery in 2015, and following their assumption that the percentage of dark matter was massive in this galaxy, they turned to what is considered to be the largest telescope on Earth at the W. M. Keck Observatory in Mauna Kea, Hawaii.

From this, they could tell from the speed of the movement of stars whether there was something there. But Dokkum released a statement about his discovery via the W.M. Keck Observatory site.

“Motions of the stars tell you how much matter there is. They don’t care what form the matter is, they just tell you that it’s there. In the Dragonfly galaxy, stars move very fast. So there was a huge discrepancy: using Keck Observatory, we found many times more mass indicated by the motions of the stars, than there is mass in the stars themselves.”

The Scientific American article explains this best.

“In other words, van Dokkum and his team found evidence of way more mass than they could actually see. Only 0.01 percent of the galaxy is made of ordinary, visible matter: stuff that is made of atoms containing protons, neutrons and electrons. But the other 99.99 percent of Dragonfly 44’s mass is the ever-elusive dark matter. Of all the stuff in this Milky Way-size galaxy, we can see almost nothing.”

Again, the other “stuff” they’re referring to are planets, stars, etc. Over time, the idea of how these surrounding objects react to dark matter, is almost a reverse way of thinking, before one realizes — with a better understanding of what dark matter is — that gravity works in the same way, as if 999 percent dark matter were an object.

Dokkum explains this view too, but he was better able to clarify this 999 percent dark matter discovery after he approached yet another location in Mauna Kea, being the Gemini Observatory where they were able to make a color image of the 999 percent dark matter-made galaxy, which is seen at the top as a smudge in our main image.

This 999 percent dark matter discovery is a further improvement on the research to learn what it is and a better understanding as to what scientists should be looking for. Already, they’re taking the next step in the research, which is further explained in the elusive discovery article we refereed to above. Surely with 999 percent dark matter, it is only elusive due to our lack of understanding?

[Image via Shutterstock]

Share this article: A Entire Galaxy Found To Be Made Entirely Of 999 Percent Dark Matter
More from Inquisitr