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Chances of Alien life in our galaxy are ‘much more likely than first thought basic chemical fact.

An artist's impression of the gas and dust in the disk surrounding the young star. The inset image, right, shows a mix of both simple and complex molecules in the vicinity of still-forming planets CREDIT: M.Weiss/Centre for Astrophysics/Harvard & Smithsonian

Chances of alien life in our galaxy are much more likely than first thought after scientists found “significant amounts” of large organic molecules surrounding young stars. Dr. John Ilee, a research fellow at the University of Leeds, who led the study, said the findings suggested that the basic chemical conditions that resulted in life on Earth could exist more widely across the Milky Way.

The team studied the discs of swirling material that surrounds stars and will eventually come together to form planets.

They found large reservoirs of precursor molecules that are “stepping stones” to complex molecules needed for life, such as sugars, amino acids, and ribonucleic acid. Each molecule emits light at different wavelengths, producing a unique spectral “fingerprint” that can be picked up by telescopes.

The team studied data from the Atacama Large Millimetre/submillimetre Array (Alma) radio telescope in Chile, looking for the molecular fingerprints surrounding new stars.

The image above shows four of the protoplanetary discs. The top row shows emissions from large dust in the discs. The bottom row shows a three-color composite image of emission from the large organic molecules HC3N (red), CH3CN (green), and c-C3H2 (blue) in each disk. Dashed circles with a radius of 50 astronomical units indicate the scale of the comet-forming region in our own Solar System CREDIT: Dr. JD Ilee/University of Leeds

Dr. Ilee said: “Alma has allowed us to look for these molecules in the innermost regions of these disks, on size scales similar to our solar system, for the first time. Our analysis shows that the molecules are primarily located in these inner regions with abundances between 10 and 100 times higher than models had predicted.”

Crucially, the disc regions in which the molecules were found are also where asteroids and comets form. Many scientists believe that life was seeded on Earth through bombardment by asteroids and comets containing large organic molecules.

It suggests that the same mechanism may be at work throughout the galaxy and beyond. “The key result of this work shows that the same ingredients needed for seeding life on our planet are also found around other stars,” said Dr. Catherine Walsh, from the school of physics and astronomy at the University of Leeds.

“It is possible that the molecules that are needed to kickstart life on planets are readily available in all planet-forming environments.” The team now wants to find out whether more complex molecules exist in the star discs. Dr. Ilee added: “If we are finding molecules like these in such large abundances, our current understanding of interstellar chemistry suggests that even more complex molecules should also be observable.”

The research was published in the Astrophysical Journal Supplement Series.

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