ESO/L. Sidewalk/t. Müller (Max Planck Institute of Astronomy/HDA)
The discovery of 17 complex organic molecules on V883 Orionis protoplanetary disc, including ethylene glycol and glycolonitrile, provides a long-sought-after puzzle piece in the evolution of these molecules.
An astronome team led by Aboubacar Fadulresearcher at the Max Planck Institute of Astronomy, in Heidelberg, Germany, discovered almost two dozen complex organic molecules (MOCs) – Including the first preliminary detection of ethylene glycol and glycolonitrile – on the protoplanetary disk of the erupted protestal V883 ORION.
These substances are considered by scientists as precursors of the blocks of life construction.
Comparison of different cosmic environments reveals that abundance and complexity of molecules of this genre increase from stellar formation regions to fully evolved planetary systems. This suggests that Seeds of Life are “assembled” in space and that are well scattered.
Astronomers had already previously discovered complex organic molecules in various locations associated with the formation of planets and stars. MOCs are molecules with more than five atomsof which at least one is carbon.
Many of them are considered blocks of life construction, as amino acids e nucleic acids or your precursors.
The discovery of 17 MOCs on the V883 Orionis protoplanetary disk, including Etilenoglicol and Glycolonitriloprovides a long-sought after puzzle piece in the evolution of these molecules between the stages that precede and follow the formation of stars and their planetary formation discs.
Glyconitrile is a precursor of amino acids glycine and alanineas well as the adenine nucleic base.
The discoveries, made with the Alma (Atacama Large Millimeter/Submillimeter Array), were presented in a published last week in the magazine The Astrophysical Journal Letters.
The “assembly” of pre-biotic molecules begins in the interstellar space
The transition from a cold star to a young star surrounded by a dust and gas disc is accompanied by a Violent phase of gas in shockintense radiation and rapid gas ejection.
Such energy processes can destroy most chemistry complex “assembled” during the previous phases. Therefore, scientists have made a scenario called “reboot“In which most chemical compounds needed for the evolution of life would have to be reproduced on circusestellar discs during the formation of comets, asteroids and planets.
“Now it seems that the opposite is true“ Kamber blackScientist at the Max Planck Institute of Astronomy and Coauthor of the study.
“The results suggest that the Protoplanetary discs inherit molecules Complex from previous phases and that the formation of complex molecules can continue during the protoplanetary disc phase, ”he adds.
In fact, the period between the energy -protest -protestlar phase and the establishment of a protoplanetary disk would be, by itself, too short so that MOCs were formed in detectable quantities.
As a result, the conditions that predict biological processes can be generalizedinstead of restricted to individual planetary systems.
The astronomers found the simpler organic moleculeslike methanol, in dense dust and gas regions that precede the formation of the stars. Under favorable conditions, they may contain complex compounds that include ethylene glycol, one of the species now discovered in V883 ORION.
“We recently found that ethylene glycol can be formed by UV irradiation of ethanolamine, a molecule that was recently discovered in space,” he adds Tushar suhasariaco -author of the article and head of the Laboratory of Origins of Life of the Max Planck Institute of Astronomy.
“This discovery supports the idea that ethylene glycol can be formed in these environmentsbut also in later stages of molecular evolution, where UV irradiation is dominant ”.
More evolved agents crucial to biologysuch as amino acids, sugars and nucleic bases that make up DNA and ARN are present in asteroids, meteorites and comets within the solar system.
Ice buried – surfaced by the stars
The chemical reactions that synthesize these MOCs occur in cold conditionspreferably in cold dust grains that later coagulate to form larger objects.
Hidden in these mixtures of rock, dust and ice, they usually remain undetectable. Access to these molecules is only possible through drilling with Spatial probes or external heatingthat evaporates the ice.
In the solar system, the sun warms the comets, resulting in tails Impressive gas and dust, or hair, essentially gaseous enclosures surrounding the cometic nuclei.
That way, the spectroscopy -The dissection of light similar to a rainbow-can capture emissions from released molecules. These spectral fingerprints help astronomers identify previously buried ice molecules.
A similar heating process is occurring in the V883 Orionis system. The central star It’s still growingaccumulating gas from the surrounding disc until eventually light the nuclear fusion in its core. During these growth periods, the falling gas warms and produces intense radiation explosions.
“These explosions are strong enough to heat the surrounding disc even environments that, Otherwise, they would be coldreleasing the chemicals we have detected, ”explains Fadul.
“Complex molecules, including ethylene glycol and glycolonitrile, radiate on radio frequencies. The soul is perfectly suitable for detecting these signs,” says Schwarz.
Astronomers of the Max Planck Institute of Astronomy obtained access to this radio interferometer through ESO, which operates it in the Chilean desert of Atacama, at an altitude of 5000 meters.
Alma has allowed astronomers to locate the V883 Orionis system and seek Weak Spectral Signswhich eventually led to the detections.
More challenges ahead
“Although this result is exciting, thestill did not unravel All the signs we have found in our experts, ”says Schwarz.“ Highest resolution data will confirm ethylene glycol and glycolonitrile detections and may even reveal more complex chemicals which we just haven’t identified yet. ”
“Perhaps we also need to look at other regions of the electromagnetic spectrum to find even more evolved molecules,” says Fadul. “Who knows what we can most discover“?
