NASA’s James Webb Space Telescope has discovered the most distant galaxies ever discovered, some of which are only 300 million years old after the creation of the universe in the Big Bang, a time when the universe had only 2% of its size. current age.
The ancient galaxy was discovered by an international team of scientists responsible for the design of JWST’s two newest instruments. The first instrument, known as the Near Infrared Camera (NIRCam), has the task of observing a small portion of the night sky in the constellation Fornax.
For 10 days, NIRCam observed light from a cluster of nearly 100,000 galaxies at nine infrared wavelengths. From this dataset, the astronomers isolated the 250 faintest and reddest galaxies and targeted them with another JWST instrument: the Near Infrared Spectrometer (NIRSpec).
NIRSpec is designed to collect the light emitted by celestial bodies and decompose it into its component colors. This process creates a rainbow-like graph called a spectrum. Astronomers can scan a galaxy’s spectrum to find everything from its elemental composition, the number of stars it contains, and even its distance from Earth.
The latter is created by measuring a phenomenon known as redshift. Light from distant galaxies takes billions of years to reach our planet. During this time, the wavelength of this light gets longer and longer, slowly moving towards the “red” part of the light spectrum.
As light travels toward Earth from its source, it inevitably passes through a large cloud of interstellar gas and dust. These clouds are known to absorb certain wavelengths of light well, while allowing others to pass relatively unhindered. These disturbances create different patterns in the rainbow spectrum.
Graph showing the position and redshift of the galaxy Anton M. Koekemoer (STScI), Christopher Willmer (University of Arizona), JWST PEARLS Team Image processing: Rolf A. Jansen (ASU), Alyssa Pagan (STScI))
Scientists can determine the age and distance of distant galaxies by observing how far the patterns in their spectra have shifted from their predicted positions due to redshift.
Using this technique, scientists have discovered four very ancient galaxies found in the JWST data, believed to have formed just 300 million years after the creation of the universe in the Big Bang. This makes it 100 million years younger than the oldest galaxy ever discovered by the Hubble Space Telescope.
This means that the light detected by JWST left its source about 13.4 billion years ago, when the universe was only 2% as old as it is today. The galaxy’s record age will make it invaluable to scientists trying to unravel the secrets of the evolution of the early universe.
‘It is difficult to understand a galaxy without understanding the early period of its evolution,’ explained astronomer Sandro Takela of the University of Cambridge, co-author of the study describing the results. University of Arizona). “As with humans, much of what happens next depends on the influence of these first generations of stars.”
“So many intergalactic questions have been awaiting Webb’s transformational opportunity, and we are thrilled to play a part in unraveling this story.”
Follow IGN to stay up to date with the latest and weirdest science.
Image credit: Northrop Grumman.
Anthony is a freelance contributor covering science and video game news for IGN. He has over eight years of experience covering the latest developments in various scientific fields and has absolutely no time to fool you. Follow him on Twitter @BeardConGamer
