Webb spots most distant ring galaxy yet
Astronomers using the James Webb Space Telescope found the most distant ring galaxy known, according to Live Science. The galaxy GS18660 is seen as it appeared 2.1 billion years after the Big Bang. Outside expert Christopher Conselice said the rare shape may teach scientists about early galaxy crashes.
Astronomers using the James Webb Space Telescope found the most distant ring galaxy known, according to Live Science. The galaxy, called GS18660, is seen as it appeared 2.1 billion years after the Big Bang, with a glowing ring of new stars. The study was published September 8 in the journal Astronomy and Astrophysics.
Lead author Michele Perna of the Spanish Astrobiology Center said the team did not target GS18660 as a ring galaxy. Older Hubble images looked stretched, and Webb's sharper data revealed the ring and let the team study the system in three dimensions, Live Science reported. Researchers tracked hot gas, chemistry, and star-formation history.
The preferred explanation is a head-on crash: a smaller intruder galaxy punched through a larger disk, sending a ripple of gas outward that formed stars in a ring. The team spotted a small companion moving away at about 264 miles per second, a gas bridge between the two, and a timeline putting the impact about 17 million to 42 million years earlier in the galaxy's history. About 10% to 20% of the stellar mass in the ring formed in the past few tens of millions of years, Live Science reported.
Christopher Conselice, a University of Manchester astronomer who was not on the study, said via Live Science that such a merger snapshot is rare and that the system may teach scientists about early galaxy formation. He said the merger case looks more likely given the nearby intruder. Perna said the crash reading is the preferred scenario, not a final conclusion. A bar-driven ring remains another option the team has not ruled out.
What we know: Live Science reports a Webb study identifying GS18660 as the most distant ring galaxy yet, seen 2.1 billion years after the Big Bang, with a preferred collision origin.
What we don't: Only Live Science has reported this so far. NewsHabit hasn't seen independent confirmation.
Sources:
- Live Science — https://www.livescience.com/space/cosmology/james-webb-telescope-discovers-most-distant-ring-galaxy-ever-hinting-at-an-ultra-rare-early-universe-collision
Where outlets agree This card follows Live Science's account of the Webb ring-galaxy study, with no second outlet counted as independent confirmation.
Where they differ Live Science presents the team's preferred collision scenario for GS18660, while researchers still leave open a bar-driven ring and outside expert Christopher Conselice finds the merger case convincing.