The discovery of megagalaxies offers a glimpse of the universe after the Big Bang End-shutdown
Astronomers have discovered what appear to be massive galaxies dating to 600 million years after 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 detected even older galaxies, dating to just 300 million years from the beginning of the universe, it is the size and maturity of these six apparent megagalaxies that surprise scientists. They reported their findings on Wednesday.
Principal investigator Ivo Labbe of Australia’s Swinburne University of Technology and his team expected to find tiny baby galaxies so close to the dawn of the universe, not these giants.
“While most galaxies in this age are still small and only grow gradually over time,” he said in an email, “there are a few monsters that are rapidly moving towards maturity. It is unknown why this is the case or how it would work.”
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 may be up to 100 billion times greater than our sun, according to scientists who published their findings in the journal Nature.
However, these galaxies are thought to be extremely compact, squeezing as many stars as our own Milky Way, but into a relatively small slice of space, according to Mr. Labbe.
Mr Labbe said that he and his team did not think the results were real at first, that there could not be galaxies as mature as the Milky Way so early in time, and that they still need to be confirmed. The objects appeared so large and bright that some team members thought they had made a mistake.
“We were just blown away, kind of unbelievable,” Labbe said.
Joel Leja of Pennsylvania State University, who participated in the study, calls them “destroyers of the universe.”
“The revelation that massive galaxy formation began very early in the history of the universe turns what many of us had thought to be established science upside down,” Mr Leja said in a statement. “It turns out that we found something so unexpected that it actually creates problems for science. It casts doubt on the whole picture of early galaxy formation.”
These galaxy observations are among the first data sets to come from the $10 billion Webb telescope, launched just over a year ago. NASA and the European Space Agency’s Webb is considered the successor to the Hubble Space Telescope, approaching the 33rd anniversary of its launch.
Unlike Hubble, the larger and more powerful Webb can peer through dust clouds with its infrared vision and discover galaxies never seen before. Scientists hope to finally observe the first stars and galaxies that formed after the creation of the universe 13.8 billion years ago.
The researchers are still awaiting official confirmation via sensitive spectroscopy, careful to call these candidates massive galaxies for now. Mr Leja said that some of the objects may not be galaxies, but obscured supermassive black holes.
While some may turn out to be smaller, “the chances are good that at least some of them turn out to be” galactic giants, Labbe said. “Next year he will tell us.”
One of Webb’s first lessons is to “let go of your expectations and be ready to be surprised,” he said.
This story was reported by The Associated Press.