Everything that is happening in the Universe, especially so far away seems fascinating. So is the collision of two massive galaxies, that are hyper-luminous, that occurred just in front of astronomer’s eyes. This has been spotted for the first time and furthermore reveals much unknown information about the way everything in the Universe was created.
“Discovering a hyper-luminous starburst galaxy is an extraordinary feat, but discovering two- this close to each other – is amazing,” said Dominik Riechers, assistant professor of astronomy and lead author on the new research, which was published in the Astrophysical Journal. He added, “It’s nearly 13 billion light-years away, and in its frenzied star-forming action, we may be seeing the most extreme galaxy merger known.”
This event occurred in the Southern Hemisphere’s Dorado constellation, which is also known as the swordfish. The ADFS-27 galactic pair takes place around 12.6 billion light-years away. Astronomers saw the two galaxies in their merging. However, it took the light from the galaxies about 13 million years to reach us.
In the published paper, “Rise of the Titans: A Dusty, Hyper-luminous ‘870-micron Riser’ Galaxy at z~6, “Riechers, T.K. Daisy Leung who is a doctoral candidate, and their colleagues saw the colliding galaxies. They are likely the most massive systems in the universe ever captured. The wondrous event was captured with the Atacama Large Millimeter/submillimeter Array (ALMA), a high-elevation radio telescope in Chile. The telescope can detect the merger into one galaxy. The mentioned merger has started strong, ongoing star formation, which led to the growth of a “Titan” galaxy, according to the paper.
According to Leung, the pair of two massive galaxies was likely formed during the early cosmic time. “These massive systems in the early universe are showing us snapshots of their early evolution,” she said in the paper.
“Finding these galaxies – about 30,000 light-years apart – helps astronomers to understand how very extreme structures form, as they continue to birth stars and become even more massive,” said Riechers.
“These galactic progenitors help us to understand massive galaxies of the present day, as we’ve tried to understand how these actually form. In other words, this discovery is helping astronomers to understand the timeline of the cosmos.”
Riechers added that the systems were originally discovered by the group with the European Space Agency’s Herschel Space Observatory. However, it appeared as a red dot.
“Galaxies usually look bluer or greener. This one popped out because of its color. It was literally really red, which means it’s a brighter object at longer wavelengths and it is farther away than most galaxies,” Riechers explained.
Sometime earlier, the same group of astronomers used the ALMA radio telescope to examine the red dot which resulted in seeing two massive galaxies that have about 50 times the amount of star-forming gas, compared to the Milky Way. Riechers said that this huge amount of gas will convert into the new stars quickly, while the pair of merging galaxies produce stars at a “breakneck pace,” which is about 1,000 times faster compared to the Milky Way.
Leung added that the ALMA telescope has “revolutionized” our comprehension of young galaxies thanks to its unprecedented resolution. “We now can see distant galaxies in exquisite detail, as we were able to uncover the compact, starburst nature of this merger pair- known only as a dusty blob in the good old days.”