After the publication of the first official full-size images and spectroscopic data from the James Webb Space Telescope, more and more new images from a state-of-the-art space observatory are emerging. Among them are observations of what could be the farthest observed galaxy. Researchers believe that the light of the galaxy GLASS-z13 dates back to a time when the universe was only 300 million years old.
An analysis of the latest data collected by the James Webb Space Telescope (JWST) has revealed a galaxy that dates back just 300 million years after the Big Bang. This is the oldest galaxy we have ever seen. The previous oldest identified galaxy found by the Hubble Space Telescope is called GN-z11 and dates back 400 million years after the birth of the universe.
The discovery article has been submitted to The Astrophysical Journal Letters and is awaiting review. It is currently available in the arXiv preprint database (arXiv: 2207.09434v1).
Galaxy GLASS-z13
The galaxy GLASS-z13 was discovered next to another very distant galaxy, GLASS-z11, whose light dates back 420 million years after the Big Bang. Together with the former farthest galaxy record holder GN-z11 and another contender called HD1, the objects suggest that there may be a population of very bright ancient galaxies that formed many stars very quickly.
These findings will still have to be confirmed. “We are potentially looking at the farthest starlight anyone has ever seen,” said Rohan Naidu of the Harvard Center for Astrophysics. And the more distant objects are from us, the longer it takes for their light to reach us, and therefore looking back into the distant universe is a look into the deep past.
The light from GLASS-z13 took 13.4 billion years to reach us, but the distance between us is now 33 billion light years due to the expansion of the universe. And although the galaxy GLASS-z13 existed in the earliest era of the universe, its exact age remains unknown. It could have formed at any point in the first 300 million years after the Big Bang.
Scientists managed to identify some of the object’s properties. According to them, GLASS-z13 has a mass of one billion Suns. Considering how quickly the galaxy formed after the Big Bang, this is quite surprising. “It’s something we don’t really understand,” admitted Naidu.
Promises of great discoveries
The galaxy was captured by near-infrared imaging devices called NIRcam (Near Infrared Camera). The ancient galaxy in the images looks like a blot of red with white in the center, and is part of a larger image of the distant cosmos known as Webb’s First Deep Field. This photo was shown to a wide audience by US President Joe Biden the day before the official publication of the first package of photos and spectroscopic data (more on this in the text: The US President showed the first deep space image made by JWST).
“Astronomical records are already crumbling and more are uncertain,” NASA’s Thomas Zurbuchen tweeted. “I only cheer when the scientific results are clear, peer-reviewed. But these discoveries look very promising, ‘he added.
Naidu and his colleagues worked on the image — a team of 25 astronomers from all over the world. The researchers acknowledged that another team of astronomers led by Marco Castellano who worked on the same data came to similar conclusions.
One of the great promises of the JWST is that it will be able to spot the earliest galaxies that formed after the Big Bang, 13.8 billion years ago. Because they are so distant from Earth, before the light emitted by them reached us, it was stretched by the expansion of the Universe and shifted into the infrared region of the light spectrum, which Webb detects with unprecedented sensitivity.
The team of researchers intends to ask Webb’s managers to use the equipment to perform spectroscopy — an analysis of light that reveals its detailed properties — to measure the exact distance to GLASS-z13, but working time with JWST will be difficult. As part of the observation campaign launched by the official presentation of the first photos, the Space Telescope Science Institute, which manages the observatory, has already allocated about 6,000 hours of observing time.
Source: New Scientist, AFP,
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