Images of six candidate massive galaxies, seen 500-800 million years after the Big Bang. One of the sources (bottom left) could contain as many stars as our present-day Milky Way, but is 30 times more compact. Credit: NASA, ESA, CSA, I. Labbe/Swinburne University of Technology. Image processing: G. Brammer/Niels Bohr Institute’s Cosmic Dawn Center at the University of Copenhagen
Key points:
- Six massive galaxies discovered in the early universe are challenging scientists' earlier understandings.
- Scientists discovered objects as mature as the Milky Way using the first dataset released from NASA's James Webb Space Telescope.
- The team hopes to confirm their findings with a spectrum image of the massive galaxies.
The discovery of six massive galaxies in the early universe is challenging scientists' previous understandings about the origins of galaxies in the universe.
“These objects are way more massive than anyone expected,” said Joel Leja, assistant professor of astronomy and astrophysics at Penn State, who modeled light from these galaxies. “We expected only to find tiny, young, baby galaxies at this point in time, but we’ve discovered galaxies as mature as our own in what was previously understood to be the dawn of the universe.”
Using the first dataset released from NASA's James Webb Space Telescope, the international team of scientists discovered objects as mature as the Milky Way when the universe was only 3% of its current age, about 500-700 million years after the Big Bang.
According to the paper published in Nature, the newly discovered galaxies are so massive that they are in contradiction with 99% percent of models for cosmology. Accounting for such a high amount of mass would require either altering the models for cosmology or revising the scientific understanding of earlier galaxy formation. Either scenario would require a fundamental shift in the current understanding of how the universe evolved.
“When we got the data, everyone just started diving in and these massive things popped out really fast,” Leja said. “We started doing the modeling and tried to figure out what they were, because they were so big and bright. My first thought was we had made a mistake and we would just find it and move on with our lives. But we have yet to find that mistake, despite a lot of trying.”
One way to confirm the team’s finding, Leja says, is to take a spectrum image of the massive galaxies, which provides more detailed data such as true distances, gasses and other elements that made up the galaxies. The team could then use the data to model a clearer picture of what the galaxies looked like, and how massive they truly were.