Astronomers recently searched the gas clouds of unborn stars for chemicals that could seed future planets with the building blocks of life.
Astronomers Yuxin Lin and colleagues have discovered organic molecules called methanimines dotting a dense clump of gas and dust 554 light-years away. The cloud, called L1544, was discovered within the Taurus Molecular Cloud and will eventually become a star with a planetary system. If Lin et al.’s research is correct, they exoplanet It can be formed with a “starter kit” of organic molecules such as methanimine. This is thanks to the chemical reactions currently taking place inside the cold, dormant molecular cloud.
Astronomers have discovered methanimine in a surprising range of locations across the universe, all the way to extremely hot and turbulent places like the Earth’s core. newborn star Even particles of frigid ice floating in interstellar space. One of the most interesting places where methammine has been discovered is in what astronomers call prostar nuclei. This is a dense mass of gas and dust on the verge of collapsing under its own gravity to form a newborn star. Think of a prestellar core like L1544, located 554 light-years away, as all the elements of a star system that require some degree of assembly.
organic chemistry starter kit
Methamine (CH2NH2) is not to be confused with the one featured on “Breaking Bad.” Like organic chemistry, it’s a very simple molecule. It sits roughly in the middle of a chain of chemical reactions between a few floating atoms and an amino acid, one of the much larger organic molecules that combine to form proteins. And even if you break down the methanimine molecule, there are still some important components in the chemistry of life left, such as carbon, hydrogen, and nitrogen.
Understanding how molecules like methanimine form in the cores of prostars like L1544 could shed new light on how planetary systems obtain their “starter kits” of raw materials for organic chemistry, from raw elements to complex molecules. like amino acids.
Habitable world, assembly may be required
Essentially an early form of a massive star, L1544 is a surprisingly quiet place. This is part of the Taurus Molecular Cloud, where other dense clumps of material like L1544 collapse under their own gravity to form new stars, each hundreds of thousands of times more massive than the star. solar.
But for now, L1544 is a quiet backwater. Material falls gradually from the warm edges of the mass inward to the cold, dense center, but it’s a very slow rain, like the calm before the thermonuclear storm of star formation.
In other layers of the cloud, the material is less dense, but the temperatures are warmer, and most of the methanimine is likely to be formed. As material from these outer layers falls inward toward the center, methanimine is distributed almost throughout the prostar core. Therefore, methanimine will likely continue to form until the moment of collapse, and some of it will probably remain in the outer part of the planetary disk that will someday orbit a brand new star.
As planets gradually coalesce out of the disk, many may have amino acid building blocks baked into them, molecules that could eventually give rise to life if a habitable planet is found among them.
“This shows that important prebiotic nitrogen and carbon chemistry remains active during the cold, quiescent phase that precedes decay, ensuring that organic precursors such as CH2N2 are inherited by the next generation of forming stars and planets,” Lin and colleagues wrote in a recent paper.
Lin et al. presented their research results. Published in “The Astrophysical Journal Letters”.