The scientists used the new observationsTo find half a dozen galaxies after the Big Bang. The distant masses of stars are so massive that they may force us to rethink the origin of galaxies.
“These objects are much larger than anyone expected,” Penn State astronomy professor Joel Leja said in a statement. “We expected to find only small, young, infant galaxies at this time, but we have found our mature galaxies in what was previously understood to be the dawn of the universe.”
The galaxies appear to be about 13 billion years old, meaning they were already mature 500 million to 700 million years after the Big Bang.
“The revelation that massive galaxy formation began very early in the history of the Universe improves what many of us thought was settled science,” Leja said. “We informally call these objects ‘universe breakers’ — and they live up to their name so far.”
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The galaxies are so massive that they seem impossible under 99% of models for the early universe, Leja said. After the Big Bang, it’s more complete than most of the math can account for.
The next-generation Web Lab allows scientists to see further back in cosmological time than they ever could before. The international team of astronomers behind the discovery worked with data from Webb’s first batch of observations last year. Their findings are published in this week’s Journal Nature Magazine.
“Once we got the data, everybody started jumping in and these massive things came out really fast,” Leja said. “We started modeling and trying to figure out what they were because they were so big and bright. My first thought was that we’ve made a mistake and we’ll figure it out and move on with our lives. But we still haven’t. We’ve tried hard to find the mistake.”
However, it’s still possible that the researchers are actually seeing something else.
Theoretical physicist Ethan Siegel, who was not involved in the research, points out that confirming the age and size of such massive galaxies would require a more detailed look at the light they emit with an instrument such as an infrared spectrometer.
“Without spectroscopy, these objects are only ‘high redshift candidates,’ meaning they can be confirmed from very early in the universe’s history, but they could also be intrinsically reddened galaxies. This happens much later in the universe,” Siegel said in an email. “However, JWST is teaching us that galaxies appear to be growing faster and more evolved at earlier times than most astronomers expected.”
Lieja agreed and emphasized that they try to keep an open mind.
“I think there is a real possibility that some of these objects could become hidden supermassive black holes,” Leja said. “Regardless, the amount of mass we found means that the known mass in stars during this period of our universe is 100 times greater than we previously thought. Even if we cut the sample in half, it’s still a striking change.”