The Milky Way Could Be a Cannibal Galaxy
When you look at the night sky, do you see clusters of stars born in our galaxy and living peacefully for millions of years? Or do you see the debris of another galaxy that has been eaten by our galaxy and its remnants are scattered around? As strange as it may sound, astronomers have found evidence for the second question.
Solving the “unsolved” case of the lost galaxy; perhaps through the Gaia mission to Europe, gives astronomers a glimpse into our galaxy’s history of cannibalism.
Gaia was launched into space in 2013 to measure the exact position and motion of billions of stars in the Milky Way galaxy. Using data from the first 22 months of the mission, the researchers examined the 3D motions of 7 million stars moving towards our local galaxy cluster.
It was observed that 30 thousand of the 7 million stars were moving strangely.
According to a study published in Nature magazine on 31 October 2018, 30 thousand of these 7 million stars were observed to be moving strangely. Based on this, it was deduced that a galaxy very close to our galaxy was eaten by our galaxy about 10 billion years ago.
“The star clusters we found with Gaia have all the features we would expect from the remnants of a galaxy merger,” said Amina Helmi, of the University of Groningen, the Netherlands, and lead author of the new study. They expressed in the form.
Ultimately, the Gaia observations, Amina and her team observed that these 30,000 stars elongated their orbits as they moved in the opposite direction to the stars in the galaxy. This situation drew the attention of researchers.
In another statement, Carine Babusiaux from Grenoble Alpes University said, “When we completed the Gaia data with information on the chemical formation of stars and the ground-based APOGEE research data, we were sure that we were just explaining.” expressed in the form.
Galaxies form stars with their chemical constituents, which is like chemical fingerprints, and the star clusters found do not have the same chemical components compared to other stars in our galaxy.
Moreover, the team discovered 13 more globular clusters acting similarly, indicating that this ingested galaxy is considerably large and possibly the same size as one of the two satellite galaxies of the Magellanic Clouds.
This discovery is a newly discovered important piece of the puzzle that will solve the evolutionary path of our galaxy over billions of years. Indeed, even though scientists know that galaxy-eating galaxies (galaxies collide, merge, grow) exist, this is evidence of the greatest “unification” in the history of our galaxy.
“Gaia was made to seek answers to such questions. We can now say how the galaxy formed in the early stages. This is also a very beautiful and wonderful thing that feels so big and so small, ”he said.