The oldest known galaxies finally spotted thanks to NASA's Webb Telescope, astronomers confirm
The oldest known galaxies are not a mystery thanks to James Webb Space Telescope. Astronomers confirmed these galaxies.
Using JWST, astronomers have confirmed the distances of some of the most distant galaxies ever. One of them took its place just 330 million years after the Big Bang and is one of the first galaxies to shine in our universe.
The galaxy is called JADES-GS-z13-0 and is currently 33 billion light years away from us. The JWST Advanced Deep Extragalactic Survey (JADES) focused on the area in and around the Hubble Space Telescope's Ultra Deep Field. Scientists have confirmed the distance of this object and three others that are not as far away but still very far away.
There are several methods of measuring how far away a galaxy actually is. A quick and easy method is to look at the colors: the redder, the further away. This is because the universe is expanding. As space-time expands, the wavelengths of light traveling the intergalactic distances shift towards the red end of the spectrum. This value is called redshift, and the color approach provides photometric redshift.
The photometric redshift for these four galaxies was very close to the true value obtained by spectra. Very good news for photometric approaches that have potentially identified the most distant galaxy ever seen (but we await confirmation of the spectroscopic redshift). So this study tells us that these four galaxies are some of the oldest objects we've seen in the universe, from when the cosmos was less than 400 million years old.
Astronomer and co-author Emma Curtis-Lake of the University of Hertfordshire in the United Kingdom said “It was crucial to prove that these galaxies do, indeed, inhabit the early universe. It’s very possible for closer galaxies to masquerade as very distant galaxies,” said astronomer and co-author Emma Curtis-Lake from the University of Hertfordshire in the United Kingdom. “Seeing the spectrum revealed as we hoped, confirming these galaxies as being at the true edge of our view, some further away than Hubble could see! It is a tremendously exciting achievement for the mission.”
