By analyzing data from the first images of a known early galaxy taken by NASA’s James Webb Space Telescope (JWST), Cornell University astronomers have discovered a companion galaxy that was previously obscured by the light of the foreground galaxy; Its young age, estimated at 1.4 billion years, has already formed many stellar generations.

Scanning the first images of a known early galaxy taken by NASA’s James Webb Space Telescope (JWST), Cornell astronomers were intrigued to see a bright spot near its outer edge.

The initial focal points and infrared observatory target were SPT0418-47, one of the brightest dusty star-forming galaxies in the early universe; Its distant light is bent and magnified by the gravity of the forward galaxy into a circle called the Einstein ring.

But a deeper dive into the initial JWST data released last fall led to a surprising discovery: a satellite galaxy formerly hidden behind the light of the foreground galaxy appears to contain several generations of stars despite its surprisingly young age, estimated at 1.4. billions of years

“We found that this galaxy is super rich in chemicals that none of us expected,” said Bo Peng, an astronomy doctoral student who led the data analysis. “JWST changes our perspective on this system and opens up new opportunities to study how stars and galaxies formed in the early universe.”

Peng is lead author of “Discovery of a Dusty, Chemically Mature Companion to the z~4 Starburst Galaxy in Early JWST Science Data,” recently published in Astrophysical Journal Letters. old By members of the Faculty of Arts and Sciences, Department of Astronomy.

Amit Vishwas said that previous images of the same Einstein ring captured by the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile contain clues to a spouse clearly identified by JSWT, but cannot be interpreted as anything more than random noise. . . ’19, research fellow at the Cornell Center for Astrophysics and Planetary Sciences (CCAPS) and co-author of the paper.

By examining the spectral data embedded in each pixel of the images from JWST’s NIRSpec instrument, Peng identified a second new light source inside the ring. He determined that the two new sources were images of a new galaxy gravitationally lensed by the same foreground galaxy responsible for the ring, although they were eight to 16 times dimmer, as proof of the power of JWST’s infrared vision.