James Webb Telescope identifies diverse primordial galaxies

The first images from COSMOS-Web, the largest observation program from the James Webb Telescope's first year of operation , have been published. Conducted by 100 astronomers from different countries, the initiative is just beginning, but it has already yielded images of spiral galaxies, gravitational lensing and even evidence of galactic mergers.

The program provided the widest area ever observed by Webb in its first year of operation, with data on galaxies in different types of environments. “The final COSMOS-Web image contains around 25,000 galaxies, an even larger number than the Hubble Ultra Deep Field [image] ,” said Caitlin Casey, principal investigator of the initiative.

Despite being one of the largest photos ever captured by the new observatory, the first image of the program represents only 4% of what the complete survey will be able to offer. The photos are mosaics formed from telescope observations taken in early January; others should take place in December this year and January 2024.

"What we thought were compact objects, based on the best images we had so far, James Webb's observations may show that these objects have multiple components and in some cases even reveal the full morphology of these extragalactic sources," said Santosh Harish , member of the program. "With these first observations, we're barely past the tip of the iceberg of what's to come with the finalization of the program."

 The program was created to map the oldest structures in the universe by surveying up to a million galaxies. For this, three main scientific objectives were determined: one of them is to improve the understanding of the Era of Reionization, name given to the period between 200 thousand and one billion years after the Big Bang, through the detection of galaxies .

Another objective is to identify and characterize ancient and massive primordial galaxies, in the first two billion years of the universe and, finally, to study the evolution of dark matter in galaxies, along with its relationship with visible matter.

The images captured for the program were made available in high resolution on the COSMOS website .

Source: arXiv ; Via:  Rochester Institute of Technology

1_COSMOS-Web/Kartaltepe, Casey, Franco, Larson, et al.

2_ First epoch of program observations, with data from the MIRI instrument, by Webb (Image: Reproduction/COSMOS-Web/Kartaltepe, Casey, Harish, Liu, et al./RIT/UT Austin/IAP/CANDIDE

3_Observations from the first season of the COSMOS-Web program (Image: Reproduction/COSMOS-Web/Kartaltepe, Casey, Franco, Larson, et al./RIT/UT Austin/IAP/CANDIDE)