Dancing galaxies make a monster on the cosmic dawn

Quasars are vivid objects powered by matter falling right into a supermassive black hole at the middle of a galaxy within the early Universe. Essentially the most accepted theory is that when two gas-rich galaxies merge to form a single larger galaxy, the gravitational interaction of the 2 galaxies causes gas to fall towards the supermassive black hole in a single or each of the galaxies, causing quasar activity.

To check this theory, a global team of researchers led by Takuma Izumi used the ALMA (Atacama Large Millimeter/submillimeter Array) radio telescope to review the earliest known pair of close quasars. This pair was discovered by Yoshiki Matsuoka, at Ehime University in Japan, in images taken by the Subaru Telescope. Positioned within the direction of the constellation Virgo, this pair of quasars existed in the course of the first 900 million years of the Universe. The pair is dim, indicating that the quasars are still within the early stages of their evolution. The ALMA observations mapped the host galaxies of the quasars and showed that the galaxies are linked by a “bridge” of gas and dirt. This means that the 2 galaxies are in truth merging.

The ALMA observations also allowed the team to measure the quantity of gas, the fabric for brand spanking new star formation. The team found that the 2 galaxies are very wealthy in gas, suggesting that along with more vigorous quasar activity in the longer term, the merger may even trigger a rapid increase in star formation, referred to as a “starburst.” The mix of starburst activity and vigorous quasar activity is anticipated to create a super-bright object within the early Universe referred to as a monster galaxy.