New Delhi: Researchers have discovered an abundance of a carbon-storing molecule called pyrene, which belongs to a class of molecules known as polycyclic aromatic hydrocarbons (PAHs), within a distant interstellar cloud of gas and dust, the raw material from which new star systems are born. Our solar system is believed to have been formed from a similar cloud of gas and dust about 4.5 billion years ago. Pyrene was found in recent analysis of the samples retrieved by asteroid Ryugu, supporting the hypothesis that much of the carbon in our own solar system were derived from pyrene.
PAHs contain rings of carbon atoms, and are believed to make up between 10 and 25 percent of the carbon in space. Infrared telescopes began revealing PAHs in the vicinity of supernova remnants or planetary nebulae which are what is left behind after a star dies in a violent explosion where its outer layers are energetically ejected into the surrounding space, as well as stellar nurseries where new stars are being born. The discovery of pyrene in the samples retrieved from asteroid Ryugu, made the researchers look for pyrene in space. Pyrene is however invisible to radio astronomy.
Synthetic cyanopyrene
The researchers instead focused on a cyanopyrene, a molecule that forms when pyrene interacts with cyanide. To be able to detect the molecules over interstellar distances, the researchers had to determine the type of signals cyanopyrene emits in space. The researchers produced synthetic cyanopyrene in the lab, and then analysed the signals the molecules emitted in the same conditions as space. The researchers found trace quantities of cyanpoyrene in the molecular cloud designated as TMC-1, about 460 million lightyears from the Earth. Pyrene is the third-largest molecule discovered in space, and the largest discovered using radio astronomy. A paper describing the findings has been published in Science.
