The James Webb Space Telescope continues to surprise the scientific world by possibly recording the youngest galaxies that existed only 200 million years after the Big Bang. Light from these objects traveled to us for 13.6 billion years, but due to the expansion of the Universe, they are now about 34 billion light years away. However, this discovery still needs to be confirmed.
Before that, the record holder, discovered thanks to James Webb, was the galaxy JADES-GS-z14-0, which was observed in a state when the Universe was 280 million years old. The new objects have working names with the prefix GLIMPSE, indicating the research project that discovered them. They may be the earliest known galaxies to have formed in the first 150 million years after the Big Bang.
Galaxies with high redshift
The objects studied are classified as “high z galaxies” because of the significant redshift caused by the expansion of the Universe. This phenomenon increases the wavelengths of light, making them closer to the red end of the spectrum. The larger z, the more distant and older the light source. For example, a redshift of z=14.2 for JADES-GS-z14-0 means that the light has traveled 13.2 billion years.
The new GLIMPSE objects have z=16-18, making them potentially the oldest galaxies known to science.
Gravitational lensing is the key to discovery
The GLIMPSE study has made such advances because of gravitational lensing predicted by Einstein. Massive objects, such as the Abell S1063 galaxy cluster, warp space-time and increase the visibility of distant galaxies beyond them. Thanks to this phenomenon, JWST was able to capture the light of such faint objects that they simply would not have been seen without lensing.
New discoveries and perspectives
Research team leader Vasily Kokorev notes that the telescope has discovered more galaxies with high z’s than expected. This suggests a higher density of early galaxies in the young Universe. At the same time, their weak luminosity and small size make it difficult to study them in detail. Accurate analysis requires spectral data, and this remains a challenge even for James Webb.
Despite its limitations, GLIMPSE promises new discoveries. Further observations are now underway that may provide further insight into the early history of the Universe.
Earlier we covered the number of galaxies in the Universe.
Provided by Space
