https://phys.org/news/2020-05-astronomers-cosmic-billion-years.html Astronomers see 'cosmic ring of fire,' 11 billion years ago: Please Register or Log in to view the hidden image! This is an artist's impression of the ring galaxy. Credit: James Josephides, Swinburne Astronomy Productions Astronomers have captured an image of a super-rare type of galaxy—described as a "cosmic ring of fire"—as it existed 11 billion years ago. The galaxy, which has roughly the mass of the Milky Way, is circular with a hole in the middle, rather like a titanic doughnut. Its discovery, announced in the journal Nature Astronomy, is set to shake up theories about the earliest formation of galactic structures and how they evolve. "It is a very curious object that we've never seen before," said lead researcher Dr. Tiantian Yuan, from Australia's ARC Centre of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3-D). "It looks strange and familiar at the same time." The galaxy, named R5519, is 11 billion light-years from the Solar System. The hole at its centre is truly massive, with a diameter two billion times longer than the distance between the Earth and the Sun. To put it another way, it is three million times bigger than the diameter of the supermassive black hole in the galaxy Messier 87, which in 2019 became the first ever to be directly imaged. "It is making stars at a rate 50 times greater than the Milky Way," said Dr. Yuan, who is an ASTRO 3-D Fellow based at the Centre for Astrophysics and Supercomputing at Swinburne University of Technology, in the state of Victoria. Please Register or Log in to view the hidden image! This is a composite image of the ring galaxy R5519 compiled from single-color images taken by the Hubble more at link..... the paper: https://www.nature.com/articles/s41550-020-1102-7 A giant galaxy in the young Universe with a massive ring Abstract In the local (redshift z ≈ 0) Universe, collisional ring galaxies make up only ~0.01% of galaxies1 and are formed by head-on galactic collisions that trigger radially propagating density waves2,3,4. These striking systems provide key snapshots for dissecting galactic disks and are studied extensively in the local Universe5,6,7,8,9. However, not much is known about distant (z > 0.1) collisional rings10,11,12,13,14. Here we present a detailed study of a ring galaxy at a look-back time of 10.8 Gyr (z = 2.19). Compared with our Milky Way, this galaxy has a similar stellar mass, but has a stellar half-light radius that is 1.5–2.2 times larger and is forming stars 50 times faster. The extended, diffuse stellar light outside the star-forming ring, combined with a radial velocity on the ring and an intruder galaxy nearby, provides evidence for this galaxy hosting a collisional ring. If the ring is secularly evolved15,16, the implied large bar in a giant disk would be inconsistent with the current understanding of the earliest formation of barred spirals17,18,19,20,21. Contrary to previous predictions10,11,12, this work suggests that massive collisional rings were as rare 11 Gyr ago as they are today. Our discovery offers a unique pathway for studying density waves in young galaxies, as well as constraining the cosmic evolution of spiral disks and galaxy groups.
CORRECTION: After reading further, the title is slightly misleading. It is not the first discovered "ring galaxy"It is the first discovered in the early universe. extract: "The evidence suggests it is a type known as a "collisional ring galaxy", making it the first one ever located in the early Universe"
