Because it could help explain why life essentially picks one molecular orientation over another. Of the three spectral lines that researchers needed to identify, only two could be observed from West Virginia due to satellite radio interference in the Northern Hemisphere, which is why the Parkes radio telescope was needed to verify the finding.
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The scientists in the new study used radio telescopes to ferret out the chemical details of molecules in the distant, star-forming cloud of gas and dust.
Molecules have biological advantage by skewing left or right.
The shocking discovery of such “chiral molecules” in deep space could lead to groundbreaking discoveries of development of life on Earth. As a result, astrobiologists studying the possible emergence of life on other planets are keen to understand where prebiotic chiral molecules are formed in the universe. The two forms – left-handed and right-handed – behave exactly the same way in terms of freezing point, melting point and light absorption capacity. “When you shake somebody’s hand, your right hand shakes another right hand, and it forms that nice, interlocking gesture; if you try to shake a left hand with your right hand it’s a little awkward because the interaction is different”, said McGuire said. A gas of chiral molecules will rotate the polarization of light passing through, which is how chirality was first discovered in the 19th century. “And it could shed light on one of most poorly-understood properties of life on Earth”.
Some organic molecules display a chemical property known as chirality, which allows them to have mirror-image versions of themselves, like a pair of human hands. They build more complicated structures due to congruence. “DNA’s double helix structure is based entirely on the fact that it uses right-handed sugars for the backbone”.
For the first time ever, scientists have detected a complex organic molecule called a chiral molecule in the reaches of interstellar space, and the discovery could greatly enhance our understanding of how biological life came to be on Earth – and maybe even life’s prospects for evolving elsewhere in the galaxy.
Now a team led by Brett McGuire of the National Radio Astronomy Observatory in Virginia and Brandon Carroll at the California Institute of Technology have detected the first chiral molecule in interstellar space.
Of the 180 interstellar molecules discovered so far, the chiral propylene oxide molecule is the first that offers clues to the mystery of homochirality.
The molecule in question, propylene oxide, was discovered in a big gas cloud called Sagittarius B2, located about 390 light-years from the centre of the Milky Way. Detecting Propylene oxide in interstellar space has opened the door for further experiments that may go a long way in determining where and how molecular-handedness emerges.
“Ideally we should strive to detect other chiral species, especially those of interest in biology or found in meteorites”, said NASA Goddard astrophysicist Stefanie Milam, who wasn’t involved in the study. This presents a challenge for researchers trying to determine if one version of propylene oxide is more abundant than the other. This chemical property is known as chirality. “If we could run the tape of life again, would the same enantiomers be selected through a deterministic process, or is a random choice made that depends on a tiny imbalance of one handedness over the other?”
“We just don’t know what process is doing this”, says Carroll.
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Researchers were able to determine the presence of these particles in space by observing through the telescope and by radio observations. That would take an intense amount of research at the largest telescopes in the world like Arecibo, the Very Large Array, and the Atacama Large Millimeter/submillimeter Array, all of which have scarce telescope time (and, in some cases, funding).
