James Webb Telescope Finds Ancient Galaxy Larger Than Our Milky Way

The James Webb Space Telescope (JWST) surprisingly detected a huge galaxy in the early universe. This discovery challenges what scientists thought they knew about how the universe works. The galaxy is known as ZF-UDS-7329, and it has more stars than our own Milky Way.

What’s surprising is that it formed just 800 million years after the universe began. In the span of the universe, which is 13.8 billion years old, this is relatively young. Moreover, these stars seem to have formed without the usual dark matter that helps galaxies grow, This goes against scientists’ long-held beliefs.

While it is unclear how this came to be, this is not unlike previous times when the JWST identified unexpectedly large galaxies in the early universe. This challenges what we know about how matter formed at the onset of the universe. This may even shake up the standard model of cosmology, which is our basic understanding of how the universe works, according to Live Science.

The researchers shared their discovery on February 14th in the journal Nature.

Researchers spotted new galaxy 11.5 billion years deep into the past

Study co-author Claudia Lagos, who is an associate professor of astronomy at the International Centre for Radio Astronomy Research, pointed out that the detection of such huge galaxies so early in the span of the universe problematizes our usual understanding of how the universe works.

This is because the structures made of dark matter, which are believed to be important for keeping these early galaxies intact, shouldn’t have formed yet at this early stage of the universe’s life, Lagos explained.

Light always travels at the same speed through space, even when there is nothing in its way. Hence, when we look deep into space, we are also looking far back in time because light takes time to reach us. This is how researchers were able to use the JWST to see ZF-UDS-7329, which existed about 11.5 billion years ago.

By looking at the various colors of light emitted from the stars in this very faraway galaxy, researchers determined these stars evolved about 1.5 billion years before we saw them. This means they came into existence roughly thirteen billion years ago, as reported by Live Science.

Researchers unsure about the formation of very first galaxies

Astronomers aren’t completely certain about when the very first groups of stars began coming together to form the galaxies we can see today. However, in the past, cosmologists believed this process was slow and lasted until a few hundred million years after the Big Bang.

Current theories suggest dark matter halos, which are mysterious and invisible substances that comprise about twenty-five percent of the universe, mixed with gas to create the first beginnings of galaxies.

Over the first billion to two billion years of the universe’s existence, these early protogalaxies matured, turning into smaller dwarf galaxies. These dwarfs then began merging, gradually growing into larger galaxies like our own Milky Way, according to Live Science.