Astronomers using the James Webb Space Telescope have spotted what they believe to be the most distant galaxy ever seen – a distant red spot 35 billion light-years away.
The galaxy, named CEERS-93316, was photographed as it existed just 235 million years after the big Bangusing Webb’s Near Infrared Camera, which can go back in time to the first twinklings of the very first stars.
The new result, which is still preliminary and has yet to be confirmed by studying the galaxy’s light spectra, has already broken a previous tentative record set by the telescope just a week ago, when another team spotted GLASS-z13, a galaxy that existed 400 million years after the Big Bang.
Light has a finite speed, so the farther it has traveled to reach us, the farther it goes back in time. The wavelengths of light from the oldest and most distant galaxies are also stretched by billions of years of travel through the expanding fabric of space-time in a process known as redshift, making Webb’s sophisticated infrared cameras essential for peering into the the universe first moments.
The researchers, who presented their findings in an article published July 26 in the Preprint Database arXiv, found that the newly discovered galaxy has a record redshift of 16.7, meaning its light has been stretched to be nearly 18 times redder than if the expanding universe weren’t pushing the galaxy away from us. The results have not yet been peer reviewed.
Webb’s extreme sensitivity to infrared frequencies means that it must be isolated from disturbing heat signals on Earthand the telescope now rests in a gravitationally stable place beyond the moon‘s – known as Lagrange’s point – after being launched there from French Guiana atop an Ariane 5 rocket on Christmas Day 2021.
In the six months since Webb’s launch, NASA engineers calibrated the telescope’s instruments and mirror segments in preparation for taking the first images. Their progress was briefly halted after the telescope was unexpectedly hit by a micrometeoroid May 23-25. The impact left “incorrigible” damage to a small part of the telescope mirrorbut that doesn’t appear to have affected its performance, Live Science previously reported.
Since the telescope released its incredible first images on July 12, it has flooded the web with photos of fascinating distant objects. The newly described record image was obtained during the Cosmic Evolution Early Broadcast Scientific Investigation (CEERS) — a survey of the sky in deep field and in wide field carried out by the telescope. .
Remarkably, the researchers who found the image weren’t even looking for the farthest recorded galaxy. Instead, they were compiling a list of 55 early galaxies (44 of which had been previously observed) to study their brightness at different times after the Big Bang – a measurement that will give them important insight into the evolution of young universes.
To confirm that the galaxy is as old as its redshift suggests, astronomers will use spectroscopy to analyze the amplitude of light over a range of wavelengths for all the galaxies that Webb’s near-infrared spectrograph instrument has found so far. This device uses tiny tunable mirrors 0.1 millimeters long and 0.2 millimeters wide that only let in light from target galaxies, eliminating background radiation so astronomers can break down a galaxy’s stars by color. This effort will reveal not only the light age of galaxies but also their chemical composition, size and temperatures.
Astronomers believe that the first stars, born from the collapse of gas clouds about 100 million years after the Big Bang, were composed mostly of lighter elements, such as hydrogen and helium. Later, stars began to fuse these lighter elements to form heavier ones, such as oxygen, carbonlead and gold.
Given the breathtaking pace of Webb’s discoveries, as well as his ability to go back as far as 100 million years after the Big Bang, it’s highly unlikely to be the most distant galaxy we’ll see. The telescope will likely break many more of its own records in the coming months – and we can’t wait to see more.
Originally posted on Live Science.