Researchers have just made an unprecedented discovery as they have found, for the first time ever, a complex organic molecule called a ‘chiral molecule,’ in the outer reaches of interstellar space.
Just as in a pair of human hands, chiral molecules have two forms which have been found to possess identical structures but are considered as mirror images of one another. Interestingly, life on Earth possesses one, and only one, handedness of many types of chiral molecules, a phenomenon known as homochirality.
According to scientists, the amino acids that make up proteins in our body are ‘left-handed’.
This fascinating new finding could greatly increase our general understanding of how life began on Earth, and possible life’s prospects for life –as we know it—to evolve elsewhere in the galaxy and universe.
To date, the origin of chiral molecules was a great mystery for scientists, although many have speculated for years that the answer to our questions could be found in interstellar clouds, which main contain the necessary ingredients for the formation of our solar system and life, eventually.
In a new study, scientists used extremely sensitive radio telescopes to detect a chiral molecule called propylene oxide (CH3CHCH2O) in Sagittarius B2, a cloud of gas and dust about three million times the mass of the Sun located near the center of our galaxy, the Milky Way.
“This is the first molecule detected in interstellar space that has the property of chirality, making it a pioneering leap forward in our understanding of how prebiotic molecules are made in the Universe and the effects they may have on the origins of life,” said Brett McGuire, a chemist and Jansky Postdoctoral Fellow with the National Radio Astronomy Observatory (NRAO) in Charlottesville, Virginia.
“Propylene oxide is among the most complex and structurally intricate molecules detected so far in space,” said Brandon Carroll, a chemistry graduate student at the California Institute of Technology in Pasadena. “Detecting this molecule opens the door for further experiments determining how and where molecular handedness emerges and why one form may be slightly more abundant than the other.”
The new research was primarily conducted using the Green Bank Telescope of the National Science Foundation of the United States in West Virginia as part of the Prebiotic Interstellar Molecule Survey, with additional supporting observations taken with the Parkes radio telescope in Australia.
According to researchers, Propylene oxide was detected in the cold, outer zone of Sagittarius B2 North, instead of hot nuclei within the gas cloud. It is in this region where researchers also detected other organic compounds.
Although propylene oxide is not used in living organisms, their presence in space is a sign of the existence of other chiral molecules. But current data does not distinguish between “right hand” and “left-handed” versions of the molecule.
The finding was published in the journal Science and was also presented at the American Astronomical Society meeting in San Diego, California.