Nasa’s James Webb Space Telescope discovers bright early galaxies that until now have been hidden from view, including one that may have formed just 350 million years after the big bang.
Astronomers said Thursday that if the results are verified, this host of newly discovered stars would beat the most distant galaxy identified by the Hubble Space Telescope – a record holder that formed 400 million years after the start of the universe.
Launched last December as a successor to Hubble, the Webb telescope indicates that stars may have formed earlier than previously thought – possibly a few million years after the big bang.
Webb’s latest findings were detailed in the Astrophysical Journal Letters by an international team led by Rohan Naidu of the Harvard-Smithsonian Center for Astrophysics. The article details two unusually bright galaxies, the first thought to have formed 350 m after the big bang and the other 450 m after.
Naidu said more infrared observations would be needed by Webb before claiming a new record holder.
Although some researchers report having discovered galaxies even closer to the creation of the universe 13.8 billion years ago, these candidates have not yet been verified, scientists told a conference of NASA press. Some of these could be later galaxies mimicking earlier ones, they noted.
“It’s a very dynamic time,” said Garth Illingworth of the University of California, Santa Cruz, co-author of the paper published Thursday. “There have been many preliminary announcements of even older galaxies, and we are still trying to determine as a community which of these are likely to be real.”
Tommaso Treu of the University of California, Los Angeles, chief scientist of Webb’s science program, said the evidence presented so far “is as strong as it gets” for the galaxy that formed 350m after the big Bang.
If the findings are verified and more early galaxies are out there, Raidu and his team wrote that Webb “will prove very effective in pushing the cosmic frontier to the edge of the big bang.”
“When and how the first galaxies formed remains one of the most intriguing questions,” the researchers wrote.
Jane Rigby of Nasa, a project scientist with Webb, noted that these galaxies were “hiding just below the limits of what Hubble could do.”
“They were waiting for us right there,” she told reporters. “So it’s a nice surprise that there are a lot of these galaxies to study.”
The $10 billion observatory – the largest and most powerful telescope ever sent into space – sits in solar orbit 1.6 million kilometers from Earth. Full science operations began over the summer, and NASA has since released a series of dazzling snapshots of the universe.
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