NASA/ESA/CSA James Webb Space Telescope has been used by astronomers to find early galaxies that had stellar bars. These are elongated features of star stars that extend from galaxies’ centers into the outer discs. This was at a time in which the Universe was only 25%.
Montage of Webb images showing six examples of barred galaxies. Two of these represent the most quantitatively identified, characterized and quantified lookback times to date. Each figure’s labels at the top of the page show each galaxy’s lookback times. They range from 8.4 billion to 11 million years ago (Gyr), which is a time when the Universe was only 40% to 20% its current age. Credit: NASA/CEERS/University of Texas at Austin.
According to Professor Shardha Jogee of the University of Texas at Austin and his colleagues, “Stellar bar” plays a key role in the secular development of galaxies. They efficiently distribute mass and angular momentum as well as driving gas inflows in the circumnuclear area through gravitational torques or shocks.
“Most current-day spirals, even our Milky Way Galaxy’s, are barred.”
“Observational evidence suggests that bars may influence central gas concentrations and velocity fields of Ionized Gas, star formation activity, central bulges, and star formation activities in galaxies nearby.”
The new study was based on 348 samples of galaxies from the early Universe.
These observations were part of the Cosmic Element Early Release Science Survey (CEERS).
The researchers were able detect stars in six galaxies, two from around 11 billion years old and four from over 8 billion years.
Webb was the first to notice bars in images taken by NASA/ESA Hubble Space Telescope.
Professor Jogee stated, “I looked at the data and said that we are losing everything else!”
The Webb image shows that the bars, which were not visible in Hubble data, just pop out of the Webb photo. This is a testament to Webb’s incredible ability to detect the structure beneath galaxies.
We are looking at an entirely new system where nobody has ever used such data before. “It’s almost like entering a forest no one has been to before,” Yuchen Kay Guo, a University of Texas graduate student said.
Professor Jogee stated that bars solve the problem of galaxies’ supply chains.
A bar transports gas at high speeds into central regions, where it is quickly converted to new stars.
Bars can also be used to channel gas through the channels, which helps in growing supermassive black hole centers within galaxies.
“The discovery and subsequent evolution of bars in these early epochs has shaken up the galaxy.”
The discovery of early barbars means that galaxy evolution models have now a way to use bars to speed up the production of stars in early epochs.
This study was published by the Astrophysical Journal Letters.
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Yuchen Guo The authors and others. 2023. First look at the z >1 Bars in Rest-Frame near-Infrared using JWST Early CeERS Imaging. ApJLIn press. arXiv: 221.08658