JWST breaks record for most distant galaxy ever detected – ScienceAlert

Light that has traveled more than 13.4 billion years to reach our neighborhood in space has been confirmed to come from the oldest and most distant galaxy detected so far.

This places the most distant of these four very young objects at the dawn of the Universe, shortly after the Big Bang, a time period when the Universe was still hazy and dark and the first rays of light were penetrating in the dark

They are so detailed the JWSTLong spectroscopic observations that researchers can not only measure how far light has traveled from these galaxies, but also infer some of the galaxies’ properties.

“For the first time, we have discovered galaxies just 350 million years after the Big Bang, and we can be absolutely sure of their fantastic distances.” says astronomer Brant Robertson from the University of California Santa Cruz.

“Finding these early galaxies in such incredibly beautiful images is a special experience.”

Being able to look at the Universe earlier than we had ever seen was one of the biggest hopes for the JWST. Our understanding of the first billion years after the Big Bang is extremely limited, and finding ever-earlier objects can help shed light on this crucial time of formation.

We have models that describe how events unfolded. We believe that, before the first stars were born, the Universe was full of opaque matter; any light was scattered by free electrons and could not flow freely.

These particles gradually combined to form neutral hydrogen; when the stars began to form, they ionized the hydrogen and the light shone. This process was completed approximately 1 billion years after the creation of the Universe.

The light from these objects is very weak, as it has traveled from a long way. And, due to the expansion of the Universe, it has spread significantly to the longer, redder end of the spectrum, a phenomenon known as redshift.

JWST is the most powerful telescope ever launched into space and specializes in infrared and near-infrared light, designed to detect this redshifted light as best we can.

To obtain a reliable redshift, the light must be broken down into its constituent wavelengths, a technique known as spectroscopy. A team of researchers broke down the light from JWST’s NIRCam into nine wavelength ranges, focusing on four high-redshift galaxies, two of which were first identified by Hubble.

The new data from JWST confirms that these two galaxies are indeed among the most distant ever detected, and the other two are even further away.

“It was crucial to show that these galaxies do, in fact, inhabit the early Universe. It is quite possible that the nearest galaxies are masquerading as very distant galaxies.” says astronomer Emma Curtis-Lake from the University of Hertfordshire in the United Kingdom.

“To see the spectrum revealed as we expected, confirming that these galaxies are at the true edge of our view, some farther than Hubble could see! This is a tremendously exciting achievement for the mission.”

The two Hubble galaxies have redshifts of 10.38 and 11.58. The new JWST discoveries have redshifts of 12.63 and 13.20, the latter of which is equivalent to about 13.5 billion light years.

Other candidates at higher redshifts are currently under investigation, but have not yet been confirmed. Given that JWST hasn’t been operational for six months yet, it probably won’t be long before the record is broken.

But in the meantime, there’s plenty to do. The observations given us of these distant galaxies as part of the JWST Advanced Deep Extragalactic Survey (JADES) collected a total of 28 hours of data from a region of space in and around the famous Hubble Ultra Deep Field.

This light can tell us a lot about the conditions of the early Universe and how the first stars and galaxies formed.

“With these measurements, we can learn the intrinsic brightness of galaxies and find out how many stars they have.” Robertson says.

“Now we can start to really distinguish how galaxies come together over time.”

The researchers will present their findings at STScI First science results from JWST conference Both preprint articles can be read here i here.