The Webb Space Telescope detects the most distant complex organic molecules in the universe

This article was reviewed based on Science X’s editorial process and policies. The editors have highlighted the following attributes ensuring the credibility of the content:


peer-reviewed publication

trusted source


Astronomers using the Webb Telescope have discovered evidence of complex organic molecules in a galaxy more than 12 billion light-years away. The galaxy lines up almost perfectly with a second galaxy just 3 billion light-years from our perspective on Earth. In this false-color Webb image, the foreground galaxy is shown in blue, while the background galaxy is shown in red. Organic molecules are highlighted in orange. Credit: J. Spilker / S. Doyle, NASA, ESA, CSA

The researchers detected complex organic molecules in a galaxy more than 12 billion light-years away from Earth, the most distant galaxy where these molecules are known to exist. Thanks to the capabilities of the recently launched James Webb Space Telescope and the careful analysis of the research team, a new study provides critical insight into the complex chemical interactions that occur in the first galaxies of the early universe.

University of Illinois Urbana-Champaign astronomy and physics professor Joaquin Vieira and graduate student Kedar Phadke collaborated with researchers at Texas A&M University and an international team of scientists to distinguish between the infrared signals generated by some of the grains of most massive and largest dust in the galaxy and those of the newly observed hydrocarbon molecules.

The results of the study are published in the journal Nature.

“This project started when I was in graduate school studying very distant and hard-to-detect galaxies obscured by dust,” Vieira said. “Dust grains absorb and re-emit about half of the stellar radiation produced in the universe, making infrared light from distant objects extremely dim or undetectable through ground-based telescopes.”

In the new study, the JWST got a boost from what the researchers call “nature’s magnifying glass,” a phenomenon called gravitational lensing. “This magnification occurs when two galaxies are almost perfectly aligned from Earth’s perspective, and light from the background galaxy is warped and magnified by the foreground galaxy into a ring shape, known as an Einstein ring,” Vieira said. .

The galaxy observed by Webb displays an Einstein ring caused by a phenomenon known as gravitational lensing. Credit: S. Doyle / J. Spilker

The team focused the JWST on SPT0418-47, an object discovered using the National Science Foundation’s South Pole Telescope and previously identified as a dust-obscured galaxy magnified by a factor of about 30-35 by gravitational lensing. SPT0418-47 is located 12 billion light-years from Earth, corresponding to a time when the universe was less than 1.5 billion years old, or about 10 percent of its current age, the researchers said.

“Before we had access to the combined power of gravitational lensing and the JWST, we could neither see nor spatially resolve the actual background galaxy through all the dust,” Vieira said.

Spectroscopic data from the JWST suggest that the darkened interstellar gas in SPT0418-47 is enriched in heavy elements, indicating that generations of stars have already lived and died. The specific compound detected by the researchers is a type of molecule called a polycyclic aromatic hydrocarbon, or PAH. On Earth, these molecules are found in the exhaust gases produced by combustion engines or forest fires. Being made up of carbon chains, these organic molecules are considered the basic building blocks for early life, the researchers said.

“What this research is telling us right now and we’re still learning is that we can see all the regions where these smaller dust grains are, regions that we never could have seen before the JWST,” Phadke said. ‘The new spectroscopic data allows us to observe the atomic and molecular composition of the galaxy, providing very important information on the formation of galaxies, their life cycle and how they evolve.’

“We didn’t expect that,” Vieira said. “Detecting these complex organic molecules at such a vast distance is game-changing with regards to future observations. This work is only the first step and we are only now learning how to use it and learn its capabilities. We are very excited to see how this goes.” to finish.”

“It is extremely interesting that the galaxies that I discovered while writing my thesis would one day be observed by the JWST,” Vieira said. “I am grateful to US taxpayers, NSF and NASA for funding and supporting both the SPT and JWST. Without these tools, this discovery would never have been made.”

More information:
Justin Spilker, Spatial variations in aromatic hydrocarbon emission in a dust-rich galaxy, Nature (2023). DOI: 10.1038/s41586-023-05998-6.

About the magazine:

#Webb #Space #Telescope #detects #distant #complex #organic #molecules #universe

Leave a Comment