A violent, catastrophic collision between two galaxies has given rise to an especially uncommon ring galaxy, lurking some 11 billion mild years from the Earth. The monstrous, donut-shaped galaxy is making stars in its large ring at a fee 50 instances quicker than our dwelling galaxy, incomes it an ominous moniker Johnny and June Money would absolutely dig: The cosmic “ring of fireplace.”
In a paper, printed within the journal Nature Astronomy on Tuesday, a global workforce of scientists element the ring galaxy R5519, found after scouring knowledge from the Hubble House telescope and the W.M. Keck observatory in Hawaii. Amongst nearly 4,000 galaxies detected within the knowledge units, R5519 was one of many brightest and displayed a transparent ring construction. So the workforce investigated additional — and shortly realized they’d discovered one thing uncommon.
“It is extremely a curious object, one which we have now by no means seen earlier than,” says Tiantian Yuan, an astronomer at Swinburne College in Australia and first writer on the research. “The big gap on this galaxy was attributable to a head-on collision with one other galaxy.”
Probing the options of R5519, Yuan and her workforce started choosing up clues as to the way it fashioned. They dominated out gravitational lensing or a galaxy merger for its uncommon construction and close by, they detected a companion galaxy — G5593. They believe this cosmic neighbor is the “intruder” galaxy which will have collided with R5519 round 40 million years in the past.
The 2 galaxies will need to have smashed into one another just about head-on — a galactic bulls-eye — and it is doubtless there was already a disk of stars current in R5519. As G5593 got here swooping via the galaxy, it cut up the disk via the heart and a wave of stars expanded from the middle, as seen within the GIF above.
“The collisional formation of ring galaxies requires a skinny disk to be current within the ‘sufferer’ galaxy earlier than the collision happens,” mentioned Kenneth Freeman, an astronomer at Australian Nationwide College and co-author on the paper, in a press release.
If R5519 is attributable to an enormous collision, that may make it an especially uncommon cosmic phenomena. Just one in each 10, 000 galaxies within the native universe are fashioned in such a manner. Notably, the early universe was far more crowded so the assumption was these sort of collisions might have been extra widespread. Yuan suggests the information is telling a distinct story.
“Beforehand, folks assume we might discover extra of those collisional ring galaxies within the younger universe, just because there are extra collisions again then,” she says. “We discover that’s not the case.”
There are nonetheless some “unsolved puzzles” in regards to the ring of fireplace, Yuan says. “We have no idea if this ring was a primary ring after the collision or it was the second ring.” She’s obtained additional knowledge from W.M. Keck to resolve this subject.
Astronomers must collect extra knowledge to make certain the ring is attributable to a collision, slightly than via pure evolution. The authors of the paper write the imaging carried out by soon-to-be-launched (and recently-assembled) James Webb House Telescope will have the ability to resolve any lingering questions. Yuan says she has already found one other ring galaxy doubtless fashioned by a head-on collision — and it is a billion years older than the “ring of fireplace.