An unprecedented discovery has been made by astronomers: the earliest galaxy identified thus far, putting pressure on existing theories of galaxy formation.
The galaxy, named JADES-GS-z14-0, shines intensely in the infancy of our Universe, observed as it appeared less than 300 million years following the Big Bang. Another finding, the galaxy JADES-GS-z14-1, is found to be almost just as distant.
The findings have been reported as “unmistakable,” prompting a new examination of the Cosmic Dawn era.
“In January 2024, NIRSpec captured data of the galaxy JADES-GS-z14-0 for almost ten hours. Upon first processing the spectrum, there was clear evidence that confirmed the galaxy’s redshift at 14.32, breaking the record for the most-distant galaxy known,” explain astronomers Stefano Carniani from the Scuola Normale Superiore in Italy and Kevin Hainline from the University of Arizona.
“Analysis of the imaging reveals the galaxy spans over 1,600 light-years, suggesting that the majority of the observed light originates from youthful stars and not from a growing supermassive black hole’s vicinity. The emitted starlight indicates a mass for the galaxy in the order of several hundred million solar masses! This brings up the question: How is it possible for nature to create such a massive, bright, and expansive galaxy in less than 300 million years?”
Three separate studies have been submitted to the arXiv preprint server and await peer review. Nonetheless, all three reach the same consensus: JADES-GS-z14-0 exists, presenting a benchmark for unraveling the mysteries of the Universe’s inception.
Until recently, our knowledge about the Cosmic Dawn, the initial billion years post-Big Bang, was scant. This obscurity was due to a blanket of neutral hydrogen that scattered light, preventing its journey.
With time, this shroud was ionized and dispersed by the ultraviolet emissions from early cosmic objects, rendering space transparent by the close of the Cosmic Dawn.
The enigma of the formation of these early celestial bodies is one that the JWST seeks to solve with its capacitive infrared detection. Its ability to see through the neutral hydrogen opens a window into those early times through its Advanced Deep Extragalactic Survey (JADES), aiming to explore objects in the cosmos’s initial 650 million years.
The pattern discovered of unexpectedly large early cosmic structures has astounded us, clashing with the notion that cosmic bodies such as supermassive black holes and galaxies develop gradually over extensive periods.
The light from JADES-GS-z14-0 is rich in dust and oxygen, elements not expected to be abundant so prematurely in cosmic history. This implies the existence of stars that have undergone multiple life and death cycles by the time the Universe was 300 million years old.
Considering that the most massive stars we know of have life expectancies of a mere few million years, the existence of JADES-GS-z14-0 is not beyond the realm of possibility, but it’s an unexpected scenario scholars didn’t predict.
The peculiarities of the galaxy demand a reassessment of the early Universe, indicating that black holes alone do not account for the myriad of sources of light we see there. Surprisingly, sizeable, luminous, well-structured galaxies seem to have formed much earlier during the Cosmic Dawn.
“JADES-GS-z14-0 is now the prototype of this early Universe phenomenon,” states Carniani. “It’s incredible that the Universe could form such a galaxy in a mere 300 million years.”
The investigation led by Carniani can be found on arXiv here, with two accompanying papers detailing the galaxy’s light properties also on arXiv here and here.
Frequently Asked Questions (FAQs)
- What is the name of the earliest galaxy discovered?
- The name of the earliest galaxy discovered is JADES-GS-z14-0.
- How far back in time does the light from JADES-GS-z14-0 come?
- The light from JADES-GS-z14-0 reaches us from less than 300 million years after the Big Bang.
- Why is JADES-GS-z14-0 significant?
- JADES-GS-z14-0 is significant because its existence poses a challenge to our understanding of galaxy formation in the early Universe due to its size, brightness, and mass.
- What is Cosmic Dawn?
- Cosmic Dawn is the period in the early Universe, about a billion years after the Big Bang, when the first stars and galaxies began to form.
- How was JADES-GS-z14-0 detected?
- JADES-GS-z14-0 was detected by using the NIRSpec instrument on the James Webb Space Telescope (JWST) in infrared, which allows observation of distant and early galaxies.