Cape Canaveral, Fla. Astronomers have discovered massive galaxies formed within 600 million years of the Big Bang, suggesting that the early universe may have had a stellar fast-track that produced these “monsters”.
While the new James Webb Space Telescope has also observed older galaxies dating to within 300 million years of the beginning of the universe, it is the size and maturity of these six apparent mega-galaxies that baffled scientists. They reported their findings on Wednesday.
Lead researcher Ivo Labbe of Australia’s Swinburne University of Technology and his team expected to discover tiny baby galaxies near the beginning of the universe – and not these whispers.
“While most galaxies at this age are still small and only getting older slowly over time,” he said in an email, “there are some monsters that fast-track to maturity. Why is this or that?” How that will work is unknown.”
Each of the six objects appears to weigh billions of times more than our Sun. In one of them, the total weight of all its stars could exceed 100 billion times that of our Sun, according to scientists who published their findings in the journal Nature.
Yet these galaxies are thought to be extremely compact, squeezing in as many stars as our own Milky Way, but into a relatively small slice of space, according to Labbe.
Labbe said he and his team didn’t think the results were real at first — that there couldn’t be galaxies maturing so quickly as the Milky Way — and that they still needed to be confirmed. The objects appeared so large and bright that some team members thought they had made a mistake.
“We were mind-blown, unbelievable,” Labbe said.
Joel Leja of Pennsylvania State University, who participated in the study, calls them “universe breakers.”
“The revelation that large-scale galaxy formation began much earlier in the history of the universe is far more science than many of us thought,” Leja said in a statement. “It turns out that we have found something unexpected that really poses problems for science. It brings the whole picture of early galaxy formation into question.”
These galaxy observations were among the first data sets to come from the $10 billion Webb telescope, which launched just over a year ago. NASA and the European Space Agency’s Webb are considered the successor to the Hubble Space Telescope, which is approaching the 33rd anniversary of its launch.
Unlike Hubble, the larger and more powerful Webb can see through clouds of dust with its infrared vision and discover previously unseen galaxies. Scientists hope to finally observe the first stars and galaxies that formed after the formation of the universe 13.8 billion years ago.
Researchers are still awaiting official confirmation through sensitive spectroscopy, being careful to call these candidates giant galaxies for now. Leja said it is possible that some of the objects are not galaxies, but obscure supermassive black holes.
While some may prove to be small, “the odds are good at least some of them will emerge” from the galactic giants, Labbe said. “Next year will tell us.”
An early lesson from Webb is to “let go of your expectations and be prepared to be surprised,” he said.
