[Color composite of galaxy AzTECC71 from multiple color filters in the NIRCam instrument on the James Webb Space Telescope. (Image Credit: J. McKinney/M. Franco/C. Casey/University of Texas at Austin)]
Texas: A Ghoslike dusty galaxy which was first discovered by at least two ground-based telescopes but found missing in Hubble Space Telescope images has been captured once again by James Web Space (JWS) Telescope.
Astronomers with the COSMOS-Web collaboration had identified the object AzTECC71 as a dusty star-forming galaxy. Or, in other words, a galaxy that's busy forming many new stars but is shrouded in a dusty veil that's hard to see through—from nearly 1 billion years after the Big Bang.
The galaxy, AzTECC71, was first detected as an indistinct blob of dust emission by a camera on the James Clerk Maxwell Telescope in Hawaii that sees in wavelengths between far infrared and microwave. The COSMOS-Web team next spotted AzTECC71 in data collected by another team using the ALMA telescope in Chile, which has higher spatial resolution and can see in infrared.
The galaxy AzTECC71 however found completely vanished in the images captured by Hubble Space Telescope. The same however has reappeared in some recent images of JWS Telescope, though as a faint, yet distinct galaxy.
These galaxies were once thought to be extremely rare in the early universe, but this discovery, plus more than a dozen additional candidates in the first half of COSMOS-Web data that have yet to be described in the scientific literature, suggests they might be three to 10 times as common as expected.
"This thing is a real monster," said Jed McKinney, a postdoctoral researcher at The University of Texas at Austin.
"Even though it looks like a little blob, it's actually forming hundreds of new stars every year. And the fact that even something that extreme is barely visible in the most sensitive imaging from our newest telescope is so exciting to me. It's potentially telling us there's a whole population of galaxies that have been hiding from us", Jed said.
If that conclusion by the team which published its findings in The Astrophysical Journal is confirmed, it suggests the early universe was much dustier than previously thought.
A dusty star-forming galaxy is hard to see in optical light because much of the light from its stars is absorbed by a veil of dust and then re-emitted at redder (or longer) wavelengths. Before JWST, astronomers sometimes referred to them as "Hubble-dark galaxies," in reference to the previously most-sensitive space telescope.
For all the latest News, Opinions and Views, download ummid.com App.
Select Language To Read in Urdu, Hindi, Marathi or Arabic.
