Astronomers are doing their best to identify the first elements of the universe, but the dust of distant galaxies makes it difficult for scientists to track these galaxies and find out what they are made of.
Researchers have discovered complex organic molecules in a galaxy more than 12 billion light-years away from Earth. According to a study published in a journal Nature Scientifically, this galaxy has become the most distant in which organic compounds have been found so far.
The galaxy is less than one and a half billion years away from the Big Bang event, and study scientists from Texas A & M University and the University of Illinois Urbana-Champaign in the United States were able to discover A mysterious material that makes up the dust grains of this galaxy reflects infrared radiation.
Scientists used gravitational lensing to gather information about the galaxy known as SPT0418-47. for the press release Published by the University of Texas, the galaxy was first detected by the National Science Foundation’s South Pole Telescope in 2013 and has been studied by several observatories, including ALMA and the Hubble Space Telescope.
Detecting such distant galaxies is difficult, as “dust obscures them from the eyes of scientists,” he said. Press release University of Illinois, according to Joaquín Vieira, professor of astronomy and physics at the same university and co-author of the study.
Cosmic magnifying glasses
Vieira adds, “Dust grains absorb about half of the stellar radiation produced in the universe and re-radiate it again, which makes the infrared radiation coming from distant objects very faint or undetectable by ground-based telescopes.” In the new study, the scientists made use of what they call a “natural zoom lens” (or what is known as a gravitational lens).
Gravitational lensing is a phenomenon in physics that occurs when there is an approximation between terrestrial observation sites and a distant light source (such as a distant galaxy). The distortion and enlargement of the light coming from the distant source occurs thanks to the gravitational effect resulting from the presence of a huge mass (such as another nearby galaxy) between that distant source and the observation site. This effect causes light from the distant galaxy to bend and magnify, forming a ring around the nearby galaxy called an “Einstein ring”. This gravitational lens helps to magnify and improve our view of distant objects and provides us with valuable information about the universe.
An amazing find
Using the James Webb Space Telescope, scientists have extracted a spectroscopic signal of the complex organic compounds – “polycyclic aromatic hydrocarbons” (PAHs) – that make up some of the dust grains in the interstellar clouds of this galaxy, where they absorb and re-emit light in the infrared range. .
Polycyclic aromatic hydrocarbons are organic compounds consisting of several attached hydrocarbon rings. These hydrocarbons include a wide range of compounds that have a characteristic aromatic odour. These compounds are found in many natural and industrial sources. They are found in small quantities in the natural environment, such as oil, coal, natural gas, smoke and smog, and there are a lot of them in space.
Study leader and astronomer at the University of Texas, Justin Spilker, notes, “These large organic particles are very common in space. In the past, astronomers believed that they were good evidence of the formation of new stars. Wherever you see these particles, you will find small stars that also shine in that.” Place”.
New stars without smoke
New findings from James Webb show that “this idea may not have been entirely true in the early universe,” according to Spilker. Thanks to high-resolution images from James Webb, the team discovered many regions that contain smoke but do not form new stars, and others that contain new stars forming, but do not contain smoke. The team was able to detect the spectrum of these aromatic compounds at a wavelength of 3.3 micrometers.
The galaxy’s dust indicates the high rate of star formation in it, which is not surprising given the early period in which this galaxy existed in the age of the universe. This is the farthest discovery to date of complex aromatic molecules. Although we don’t know the reason for the inhomogeneous distribution of PAHs in that galaxy, it does promise exciting future studies of the evolution of galaxies in the early universe.