AUSTIN (KXAN) – A team of researchers from the University of Texas have discovered something unexpected in new data collected last July by the James Webb Space telescope: barred galaxies.
“It was an absolute adventure, in the sense that this is not what we were looking for,” said Shardha Jogee Ph.D. with UT’s Department of Astronomy.
Bars are long cylindrical tubes that stretch from the center of a galaxy to the outer edge. “They help to solve the supply chain problem in galaxies,” Jogee said. “They take the gas that’s in the outer part of the galaxy, they bring it to the center.”
Previous observations of barred galaxies by the Hubble Space Telescope led scientist to believe they only formed in older galaxies.
The new observations revealed they formed when the current universe was just 25% of its age now, about 11 billion years ago. Meaning they formed when many galaxies were young.
The observations were made with the James Webb Space Telescope. “We are really looking at it like it’s a time machine,” Dr. Jogee said. The telescope is the most powerful ever built and can look billions of years in the past.
Discovering early barred galaxies
The discovery was made using data from the Cosmic Evolution Early Release Science Survey (CEERS). Dr. Jogee and her team published their findings in The Astrophysical Journal Letters this month.
The UT team consisted of Jogee, Kay Yuchen Guo, Steven Finkelstein, Micaela Bagley and Maximilien Franco. Undergraduate students Eden Wise and Zilei Chen also played a role. Authors from other nations and institutions also participated in the research.
“The fact that we have seen bars early in the universe, means that a new channel to form new stars very early on in the universe,” Dr. Jogee said.
Not only do bars bring gas into the center of the galaxy to form new stars, but also to feed the super massive black hole in the center of a galaxy.
The discovery of barred galaxies this early in the universe could change how we look at the evolution of galaxies.
Why is the James Webb Space Telescope a ‘time machine’?
Webb observes space by looking at infrared light as opposed to visible light, which is what Hubble sees. Infrared light travels further than visible light and can pass through some objects in space.
The further Webb looks, the further back in time it sees. “The image we are seeing at this moment is not what the galaxy looks like now. It’s what the galaxy look like when that light left it,” Dr. Jogee said.
Light takes time to travel. You’ve probably heard of a “light year” before. That is the amount of time it takes for light to travel one year. So if something is said to be “11 Billion Light Years Away”, that means it took 11 billion years for the light to reach us.
Infrared light travels further than visible light. Because Webb sees infrared, it can see further back in time than anything else currently in orbit.
Webb has taken photos, which aren’t actually photos but a collection of data points converted into photos, from billions of years ago. Early on its mission, it took photos of some of the oldest parts of the universe.