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THE DRAGONFLY 44 GALAXY OPENS NEW DEBATE ON THE GALAXY FORMATION THEORY
IT IS A LARGE, DIM AND DIFFUSE GALAXY. he Milky Way has a dark twin galaxy called the Dragonfly 44. Discovered by Yale University astronomer Dr. Pieter van Dokkum and his colleagues a year ago, the Dragonfly 44 has recently revealed startling a direct relationship between the size of facts about the formation a galaxy and its dark of a galaxy. It primarily matter. consists of dark The Dragonfly The recent matter and is 44 is comparable discovery located 300 has annulled to the Milky Way million lightthe earlier years away from (100,000 light notion. Hence, years wide) in the Milky Way a galaxy can size. The galaxy have the same in the Coma has just 0.1 amount of cluster. It is a percent stars. It dark matter large, dim and was first detectedas the Milky diffuse galaxy. by the Dragonfly Way but could Hitherto, it Telephoto Array have hundred times fewer was believed in Toronto. stars. The that there was
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galaxy formation requires evolving a thoroughly new perspective to understand the phenomenon. The discovery of the Dragonfly 44 with its unique composition could hold new answer to understand the secret behind the dark matter, which supposedly constitutes 90 percent of the universe. The galaxy, which resembled a blob was hardly distinguishable and went unnoticed for a year. Later, looking at it through powerful telescopes, the Keck II and the Gemini North telescopes along with the Dragonfly telescope, which was designed by study authors Roberto Abraham and Pieter van
Dokkum, the researchers found something else. They found that a huge amount of gravity held the stars in place. The researchers used star velocity to measure the mass of the galaxy and reached the conclusion that the dark matter comprised 99.9 percent of its mass. With the discovery of the Dragonfly 44, a new dimension is added in understanding the elusive building block, the dark matter of the universe. Astronomers are still finding answers for the formation of a dark galaxy like the dragonfly 44. It has been observed that a relatively large segment of the stars found in Dragonfly 44 is in the form of compact clusters. The observation might serve as an important clue to the formation of a dark galaxy. Though, it is too early to come to a conclusion in this regard. Van Dokkum explains,
“Ultimately what we really want to learn is what the dark matter is�.
He feels that finding newer massive dark galaxies that are closer than the Dragonfly 44 can help astronomers better. That way, researchers can study even weak signals to reveal the constituents of the dark matter particle, which is still elusive and unidentified.