The question of the origin of life on Earth remains a real stumbling block, perhaps, at all times. Many scientists for many years trying to find the key to his answer in space, more precisely, there are looking for building material life – organic molecules.
To date in interstellar space has revealed more than 180 organic molecules, but still in sight of the researchers did not come across any chiral. This property implies the existence of a mirror molecule that is fully identical in chemical composition. Such couples are often compared for clarity with the right and left hands.
In every living organism on Earth are chiral molecules of only one type. This feature is called homochirality and is essential for many biological structures, including DNA. There is a perception that homochirality is an evolutionary advantage. It is still unclear why nature has chosen in each case, this type of molecules, and not the opposite.
Scientists believe that to solve this riddle, or at least close to it, they can figure out how chiral organic molecules formed in outer space before they settled on the comets and asteroids that straight takes them to the young habitable planets.
And finally, a decade of research success. An international team of researchers using highly sensitive radio telescopes green Bank (GBT) in the US and Australian parks found in interstellar space molecules of propylene oxide. This occurred not far from the center of our Galaxy in a cloud of star formation Sagittarius B2 (Sgr B2).
“Propylene oxide is one of the most structurally complex molecules detected so far in space, — says one of the study participants Brandon Carroll, Brandon Carroll) in the official press release. – This discovery opens the door for future experiments that will determine how there is chirality and why one form may be more common than others.”
Organic molecules in interstellar clouds are formed in several ways. In the simplest case, they face, forming a more complex compound according to the laws of gas-phase chemistry. But with increasing complexity of molecules, this process becomes ineffective.
Astronomers believe that propylene oxide could be formed by the interaction of small molecules on the surface of dust particles, covered with a crust of ice. Then, these longer and more complex education might evaporate and interact with other molecules in the surrounding gas clouds.
Each molecule leaves its distinctive signature in the radio frequency spectrum, allowing to detect from the Ground. More complex molecules leave the more complex the signature and because of this they are harder to detect and even more to prove the truthfulness of their results.
In the case of propylene oxide is necessary to observe three spectral lines, associated with the presence of the molecule. Two of them were recorded with the GBT, but the third watch in the Northern hemisphere was impossible due to the strong satellite interference. Here called parks, which allowed us to get the missing line.
Unfortunately, the available data do not allow to distinguish between enantiomers (those specular reflections of molecules), because in addition to the same chemical composition, they also have identical melting point, boiling point, freezing point, and the same spectra. “These spectra are like a shadow from your hands,” explains Carroll. – It is impossible to say, the right hand of her rejected or left”.
The researchers hope that eventually they will be able to determine if there is an excess of one of the versions of propylene oxide. To do this they plan on using the study of how the polarized light interacts with different molecules in outer space.