The equipment was used to observe a set of massive galaxies that formed around 500 to 700 million years after the Big Bang, when the universe was only 3% of its current age. Those galaxies have stellar masses up to 10 billion times that of our Sun, and one that could be as massive as 100 billion times that of our Sun.
In all, the scientists found six galaxies, which together raise the possibility of changing what scientists know about the beginnings of galaxies in our universe. The researchers refer to the objects as “universe breakers” and claim they contradict 99% of existing models of the universe.
Such galaxies would not be expected to be so large so soon after the beginning of the universe, the researchers say. The mass of the stars examined in the new research is up to 100 times greater than the researchers had previously thought.
“These objects are much more massive than anyone expected,” Joel Leja, an assistant professor of astronomy and astrophysics at Penn State, said in a statement who modeled light from galaxies.
“We only expected to find small, young, baby galaxies at this time, but we discovered galaxies as mature as our own at what was thought to be the dawn of the universe.”
If they can confirm them, they suggest that our history of the early cosmos may be wrong and that galaxies grew much faster than we assumed. That would require changing our models of the universe or our understanding of how galaxies began.
“We examined the early universe for the first time and had no idea what we were going to find,” Leja said. “It turns out that we found something so unexpected that it actually creates problems for science. It casts doubt on the full picture of early galaxy formation.”
However, scientists caution that the distance and age of the galaxies mean they can’t be absolutely sure what they are. Some could turn out to be supermassive black holes, the researchers say, but with six candidates, several of them are likely to be galaxies, as suspected.
“If one of these galaxies is real, it will push the limits of our understanding of cosmology,” said Erica Nelson, a co-author of the new research and an assistant professor of astrophysics at the University of Colorado at Boulder.
And even other objects would be just as impressive, the researchers say. “Another possibility is that these things are a different type of strange object, like faint quasars, which would be just as interesting,” Professor Nelson said.
The findings could be confirmed by taking spectrum images of the galaxies, which would help confirm how far away they are and what they are made of. That, in turn, would allow scientists to understand what they would look like and how big they are.
The new study, ‘A population of ~600 Myr red candidate massive galaxies after the Big Bang’, was published today in Nature.