Astronomers discover a swarm of galaxies orbiting a hyper-luminous galaxy
Using the Very Large Telescope and the radio telescope ALMA in Chile, a team of astronomers including researchers from the Niels Bohr Institute has discovered a swarm of galaxies orbiting the surroundings of a hyper-luminous ...
A fundamental issue in astronomy is the question of how galaxies form, grow, and evolve.
As a part of their evolution, most galaxies seem to foster a supermassive black hole in their center. These gravitational monsters occasionally swallow nearby gas and stars, spewing out excess energy as powerful jets, a phenomenon known as a quasar.
From galaxy to quasar
Many details about the transition from "normal" galaxies to quasars are still unknown. But in a new study published in Nature Communications, a team of astronomers led by Michele Ginolfi at ESO, Garching, may have come a step closer to understanding this evolution.
"Before evolving into a full-blown quasar, some galaxies are thought to go through a phase of being very dusty, and very 'active' in terms of star formation and accretion of gas onto their central, supermassive black holes," Ginolfi explains. "We set out to design an experiment to learn more about this transition phase."
Ginolfi and his collaborators focused on an already known galaxy, W0410-0913, one of the brightest, most massive and gas-rich galaxies in the distant universe, seen 12 billion years back in time.
The massive, hyper-luminous galaxy W0410-0913 and its surroundings, seen 12 billion years back in time. The zoom-in on W0410-0913 shows a map of the velocity of the gas in the galaxy, more specifically carbon monoxide gas: Blue colors mean gas coming toward us, while red means receding from us. In other words, the galaxy is rotating. Credit: M. Ginolfi & G. Jones / VLT / ESO
Galaxies in 3D: A three-dimensional stereographic view of the image shown in the beginning of this article: If you cross your eyes and focus on the blue sphere, which illustrates the galaxy W0410-0913, you should be able to get an idea the 3D position of all the other galaxies (might take a while to adjust). The squares in the back plane are 200,000 lightyears on each side The distance along the line of sight was estimated using the hydrogen Lyman alpha spectral line, but is uncertain due to the undetermined effect on the motion of the satellite galaxies by W0410-0913. Credit: Peter Laursen