Mergers of galaxies are not particularly rare, but they are important events. Not only for participating galaxies, but also for scientists trying to gather how galaxies are developing. Astronomers using ALMA have now discovered the earliest example of a galaxy merger. The pair of conflicting galaxies is called B14-65666, a clumsy name, but scientifically useful. (We'll call it "object.") The object is 13 billion light-years in the constellation Sextans. This means that the light we see now has left the site 13 billion years ago, shortly after the beginning of the universe.
This is not the first time this object has been spotted. Previously, Hubble noticed this object, but Hubble looked like two separate objects, probably star clusters. But the Millennium / Submillimeter Array team, perhaps the most sensitive radio telescope in the world, has shown that the object is two merging galaxies 1
3 billion years ago.
The results of these new observations have been published. in publications of the Astronomical Society of Japan on June 18, 2019. The name of the article is "The Big Three Dragons": az = 7.15 The Lyman Break Galaxy was discovered in [OIII] 88 um, [CII] 158 um, and the ALMA powder continuum. "Leading author of the study is Takuya Hashimoto of Waseda University, Japan.
When Hubble looks at the subject, it is confined to the ultraviolet spectrum. With this constraint, the object looked like two star clusters, one in the northeast and one in the southwest. But when Hashimoto and his team used Alma's power to study the object, they saw something else: signaling fingerprints of chemical elements.
ALMA has seen the radio waves of carbon, oxygen, and dust in the object. Detecting these three signals is the key to unlocking the nature of the object.
The analysis showed that the object really had two parts, just as Hubble saw. But the signals from carbon, oxygen and dust added another layer of information about the site, thanks to ALMA. He showed that while the two spots are different, they form a single system. Each spot moves at different speeds, indicating that they are two mergers of galaxies.