As part of the JWST COSMOS-Web survey, astronomers have reported the finding of a new galaxy using the James Webb Space Telescope (JWST). The newly discovered object, known as JWST-ER1, is a large, compact, and dormant galaxy. The results were described in a paper posted on the pre-print service arXiv on September 14.
Giant elliptical galaxies may have originated from enormous galaxies that stopped producing stars, or massive inactive galaxies. These objects could be crucial to advancing our understanding of the history of galaxies since they created stars sooner and built up their stellar masses more swiftly.
A new galaxy of this kind has been discovered, and it has been given the name JWST-ER1, according to a team of astronomers led by Pieter van Dokkum of Yale University. As part of the continuing wide and deep study of up to 1 million galaxies known as COSMOS-Web, the object was detected with JWST’s Near Infrared Camera (NIRCam). The so-called Einstein ring, a phenomenon in which light appears as a ring due to gravitational lensing, is one of the most amazing aspects of JWST-ER1.
“The galaxy and its ring were identified in JWST NIRCam observations in the context of the COSMOS-Web project, a public wide-area survey using the F115W, F150W, F277W, and F444W filters,” the researchers said.
According to NIRCam measurements, JWST-ER1 is made up of an early-type compact galaxy (JWST-ER1g) and an entire Einstein ring (JWST-ER1r) with two pronounced red concentrations. The ring’s center was estimated to have a diameter of roughly 1.54 arcseconds.
The new galaxy, which has a radius of around 21,500 light-years and an estimated mass of 650 billion solar masses, was discovered with a redshift of 1.94. The findings indicate a 1.9 billion year age and a star creation rate of only four solar masses per year. JWST-ER1 is a large and dormant galaxy as a result. Similar to other inactive galaxies at comparable redshifts, it is also fairly compact.
The ring JWST-ER1r, according to astronomers, is created by a background galaxy with a photometric redshift of 2.98. Although the majority of them are incomplete, they connect a sizable number of known Einstein rings.
The study also discovered that JWST-ER1 is almost perfectly round and that the NIRCam imaging has not shown any conspicuous star-forming regions, tidal tails, or other anomalies.
In order to determine whether adjacent galaxies or objects in its line of sight may have contributed to its mass and to determine whether JWST-ER1 is the core galaxy of a cluster’s progenitor, the authors of the research suggest additional studies of JWST-ER1.
