Space. Has the James Webb Telescope found the most distant galaxy ever observed?

It would be older than Earth. The James Webb Telescope, which recently unveiled its first photographs, may have found the most distant galaxy ever observed. The latter existed more than 13 billion years ago, compared to 4.5 billion for our blue planet.

The light from what has been named GLASS-z13 was actually emitted 13.5 billion years ago. This galaxy appears to us as it was only about 300 million years after the Big Bang, 100 million years smaller than the previously observed record, Rohan Naidu, of the Center for Astrophysics at Harvard. He is the lead author of a study analyzing data from James Webb’s early observations, which is currently underway.

The study has not yet been peer-reviewed, but released as a “preprint” to be quickly available to the expert community. It has been submitted to a scientific journal for forthcoming publication, Rohan Naidu said.

To see far is to go back in time

One of the main tasks of the James Webb Telescope is to observe the first galaxies formed after the Big Bang, which took place 13.8 billion years ago.

In astronomy, looking far is like going back in time. Sunlight, for example, takes eight minutes to reach us, so we see it as it was eight minutes ago. By looking as far as possible, we can therefore perceive objects as they were billions of years ago.

“The records in astronomy are already faltering”

Many astronomers enthusiastically commented on this discovery on social networks.

“The records in astronomy are already faltering,” tweeted Thomas Zurbuchen, NASA’s associate administrator of science. “Yes, I tend to applaud only peer-reviewed scientific findings. But this is very promising!” He added about the study.

Another research team also concluded the same results, according to Rohan Naidu, “giving him confidence”.

Already large galaxies shortly after the Big Bang

The galaxy was observed by James Webb’s NiRcam instrument and detected on what is called a “deep field”, i.e. a wider image taken with a long exposure time to detect the faintest lights.

The special thing about James Webb is only working in the infrared. The light emitted by the oldest objects has stretched and “reddened” along the way and passes into this wavelength that is not visible to the human eye.

To draw a picture of this galaxy, therefore, the data has been “translated” into the visible spectrum: it then appears as a red circular shape, rather cloudy and white in the center.

In fact, the approximately twenty scientists who participated in the study studied two galaxies, the other being called GLASS-z11, which is less distant. They have surprising properties, for the little we already know:

They appear quite massive, and this very shortly after the Big Bang. It’s something we do not really understand

Rohan Naidu, astronomer at the Harvard Center for Astrophysics

When exactly did they occur? Impossible to say at the moment. “There is still work to be done,” the researcher said. He and his colleagues requested more observation time with the telescope to perform spectroscopic analyzes – a technique for determining the properties of a distant object through the analysis of captured light. This should confirm their distance.

The James Webb Telescope was launched into space about six months ago. To the value of $ 10 billion, it was located 1.5 million kilometers from us. It has enough fuel to run for 20 years. Astronomers thus expect to be inundated with new cosmic discoveries for a long time to come.

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