Astronomers discover farthest galaxy with the James Webb Space Telescope

May 30, 2024

The following article has undergone review in accordance with Science X's editorial process and policies. Editors have focused on the following points while verifying the credibility of the content:

• Fact-checked
• Preprint
• Trusted Source
• Proofread

The proofreading was undertaken by Peter Edmonds from the Harvard-Smithsonian Center for Astrophysics.

An international team of astronomers has announced today the discovery of the earliest and the farthest galaxies ever seen, which trace back to about 300 million years after the Big Bang. They used NASA's James Webb Space Telescope (JWST) for this groundbreaking research, which marks a significant advancement in the study of the early universe.

The JWST Advanced Deep Extragalactic Survey (JADES) team made this discovery. Daniel Eisenstein of the Center for Astrophysics | Harvard & Smithsonian (CfA), one of JADES' team leads, and a Principal Investigator in the observing program that unveiled these galaxies, was aided by Ben Johnson and Phillip Cargile, both Research Scientists at CfA, and Zihao Wu, a Harvard Ph.D. student at CfA.

The stretch of light from distant galaxies to longer wavelengths because of the universe's expansion is considered an extreme effect for these two galaxies. Due to this effect, their ultraviolet light gets shifted to infrared wavelengths, which can only be detected by the JWST. Moreover, we see more distant galaxies as they existed earlier in time since light takes time to travel.

The more distant of the two record-breaking galaxies is named JADES-GS-z14-0 and the other galaxy is JADES-GS-z14-1. JADES-GS-z14-0 not only sets a new record in terms of distance but is also notable for its size and brightness.

According to Eisenstein, a Harvard professor and head of the Astronomy Department, the size of the galaxy confirms that the light produced is generated by a large number of young stars rather than by the material falling on a supermassive black hole, which would appear much smaller at the center of the galaxy.

The combination of high luminosity fueled by young stars and extreme brightness makes JADES-GS-z14-0 an unprecedented piece of evidence that supports the rapid construction of large, massive galaxies in the early universe.

Dr. Stefano Carniani of the Scuola Normale Superiore in Pisa, the lead author on the discovery paper, stated, "JADES-GS-z14-0 now becomes the archetype of this phenomenon. It is astonishing that the universe could make such a galaxy in only 300 million years."

Early galaxies showing unexpected vigorous rates of activity have been recorded in the JWST's initial images captured in its first two mission years. This trend contradicts the majority of astronomers' pre-launch expectations based on theories of galaxy formation.

When the JADES team first noticed JADES-GS-z14-0 over a year ago, its proximity to a foreground galaxy made it difficult for them to determine whether the two galaxies were close neighbors. However, after conducting five full days of deeper imaging using the JWST Near-Infrared Camera in October 2023, they were able to better isolate the sensor images of early galaxies.

Dr. Kevin Hainline, a research professor at the University of Arizona, said, "We couldn't provide any plausible explanation for this galaxy being merely a neighbor of the nearby galaxy."

This galaxy was found in a field where the JWST Mid-Infrared Instrument had conducted an ultra-deep observation. Its brightness at intermediate infrared wavelengths indicates emission from hydrogen and even oxygen atoms formed in the early universe.

Zihao Wu, a co-author of a second paper on this finding led by Jakob Helton, a doctoral candidate at the University of Arizona, said, "Despite being so young, the galaxy is already active creating elements that we are familiar with on Earth."

The team, buoyed by their findings, took a spectrum of each galaxy and confirmed their hunch that JADES-GS-z14-0 was indeed a record-breaking galaxy and the fainter candidate, JADES-GS-z14-1, was almost as far.

A third paper, led by Professor Brant Robertson from the University of California-Santa Cruz and Ben Johnson, presents a study on the evolution of this early population of galaxies.

Johnson stated, "This incredible object shows that galaxy formation in the early universe was very rapid and intense. The JWST will help us discover more such galaxies perhaps from even earlier times in the universe. It's a fantastic opportunity to study the beginnings of galaxies."

All three papers can be found on the arXiv preprint server.

Additional information: A bright cosmic dawn: spectroscopic validation of two luminous galaxies at z∼14, arXiv:2405.18485 [astro-ph.GA]

JWST/MIRI photometric detection at 7.7 μm of the stellar continuum and nebular emission in a galaxy at z>14, arXiv:2405.18462 [astro-ph.GA] arxiv.org/abs/2405.18462

Journal information: arXiv

Provided by Harvard-Smithsonian Center for Astrophysics