An analysis of new images captured by the James Webb Space Telescope (JWST) reveals for the first time galaxies with starbars at a time when the universe was only 25% of its present age. The discovery of barred galaxies at such an early time in the universe conflicts with the most accepted theories on the evolution of galaxies, so these theories will now have to be revised.
The stellar bar is a bar-shaped structure, made essentially of stars, that extends from the center of the galaxy to the outermost sector of its disk. Our Milky Way galaxy also has one.
Prior to JWST, Hubble Space Telescope images had never captured bars at such an earlier time. In a Hubble image, a galaxy from that time, EGS-23205, is little more than a disk-shaped blob, but in the corresponding recently taken JWST image, it is a perfect spiral galaxy with a clear star bar.
The analysis of the new images and the aforementioned interpretation are the work of the team led by astronomer Shardha Jogee, from the University of Texas at Austin, United States.
The JWST is the result of an international collaboration led by NASA, ESA and CSA, respectively the US, European and Canadian space agencies.
The galaxy EGS-23205 captured with the Webb Space Telescope. (Photo: NASA/CEERS/University of Texas at Austin)
Jogee and his colleagues identified another barred galaxy, EGS-24268, also from about 11 billion years ago, bringing to two the number of barred galaxies that were barred long before any of the previously discovered galaxies.
The study is titled “First Look at z > 1 Bars in the Rest-Frame Near-Infrared with JWST Early CEERS Imaging”. And it will be published in the academic journal The Astrophysical Journal Letters. (Fountain: NCYT de Amazings)