In a new incredible discovery, water has been detected in a massive galaxy located 12.88 billion light-years away from us. This is the most distant finding of a very important element for supporting life in a regular star-forming galaxy.
The large galaxy, which is called SPT0311-58, is actually two galaxies that are merging into one. They were being witnessed when the Universe was just 780 million years old – approximately 5% of its current age when the very first galaxies and stars were forming. The larger of the two galaxies contains H2O and carbon monoxide molecules which were detected by scientists who were using the Atacama Large Millimeter/submillimeter Array (ALMA).
Sreevani Jarugula, who is an astronomer at the University of Illinois and the primary investigator of the new research, explained what they found, “Oxygen and carbon, in particular, are first-generation elements, and in the molecular forms of carbon monoxide and water, they are critical to life as we know it,” adding, “This galaxy is the most massive galaxy currently known at high redshift, or the time when the Universe was still very young. It has more gas and dust compared to other galaxies in the early Universe, which gives us plenty of potential opportunities to observe abundant molecules and to better understand how these life-creating elements impacted the development of the early Universe.”
Molecular hydrogen and carbon monoxide are the two most plentiful molecules in the universe, and water comes in third on the list. Water and far-infrared emissions from dust have previously been detected in other galaxies from the early and local universe as explained by Jarugula, “The dust absorbs the ultraviolet radiation from the stars in the galaxy and re-emits it as far-infrared photons.” “This further excites the water molecules, giving rise to the water emission that scientists are able to observe. In this case, it helped us to detect water emissions in this massive galaxy. This correlation could be used to develop water as a tracer of star formation, which could then be applied to galaxies on a cosmological scale.”
Jarugula went on to say, “Early galaxies are forming stars at a rate thousands of times that of the Milky Way,” adding, “Studying the gas and dust content of these early galaxies informs us of their properties, such as how many stars are being formed, the rate at which gas is converted into stars, how galaxies interact with each other and with the interstellar medium, and more.” The study was published in The Astrophysical Journal.
Images of the SPT0311-58 galaxy can be seen here.