'Hubble 30 Years' Quickly Surpassed by JWST... Oldest Galaxy Discovered [Reading Science]'

A research team from the Harvard-Smithsonian Center for Astrophysics in the United States discovered the GLASS-z13 galaxy, estimated to have formed 13.5 billion years ago, through observation images from the James Webb Space Telescope (JWST). Photo by NASA.

[Asia Economy Reporter Kim Bong-su] The James Webb Space Telescope (JWST), which has been making new history since it began official observations, has succeeded in the first observation of the oldest galaxy discovered so far. The primordial stars, estimated to have formed about 300 million years after the Big Bang, have revealed themselves to humanity.

Dr. Rohan Naidu and his research team at the Harvard-Smithsonian Center for Astrophysics in the United States published these research results on the paper-sharing site arXiv and the international astronomy journal Astrophysical Journal Letters on the 19th (local time). The discovery of a galaxy formed 13.5 billion years ago is the first of its kind. It broke the record for the oldest galaxy observation set by the Hubble Space Telescope in 2016 with the discovery of GN-z11 in Ursa Major (about 13.4 billion years ago).

The research team obtained these results after studying observation images of the galaxy cluster ‘Abell 2744’ as one of JWST’s early research projects. Like the SMACS 0723 galaxy cluster observed in the ‘James Webb Deep Field’ previewed by U.S. President Joe Biden on the 11th, Abell 2744 has very strong gravity that distorts light, allowing observation of distant galaxies located behind it.

From the images of the Abell 2744 galaxy cluster, the research team discovered two galaxies with the most severe redshift (a phenomenon where the wavelength of light is distorted due to the expansion of the universe), naming them GLASS-z11 and GLASS-z13 respectively. This means that the two galaxies were formed about 13.4 to 13.5 billion years ago. JWST achieved this result by surveying an area slightly larger than the full moon in the night sky with its remarkably sensitive near-infrared observation instruments.

According to current analysis, both of the newly discovered galaxies have masses about one billion times that of the Sun. This is a characteristic found only in galaxies formed up to 500 million years after the Big Bang. Also, the two galaxies are very small compared to our Milky Way (about 100,000 light-years in diameter). GLASS-z13 is estimated to be about 1,600 light-years, and GLASS-z11 about 2,300 light-years in size.

Dr. Naidu explained, "If our predictions are correct, the age of the galaxies we discovered is only a few hundred million years," adding, "JWST’s amazing performance is completely changing our perspective on the universe."