According to astronomers, the biggest molecule yet discovered in a churning disc of dust and gas around a young star has been identified.

Astronomers discovered the evidence of dimethyl ether, a nine-atom chemical, in this swirling cloud. We can consider this oxygen-bearing molecule a prebiotic substance since it can operate as a building block for sugars and other biomolecules.

The finding of the chemical could have significant consequences for our knowledge of how life arises in the Universe since the disc around the star, known as IRS 48, would cluster together to produce exoplanets.

"We can learn more about the beginning of life on our planet from these observations, and so have a clearer picture of the possibility for life in other planetary systems," says Nashanty Brunken, an astronomer at Leiden University in the Netherlands.

"Seeing how these findings integrate into the wider picture is quite intriguing."

Dimethyl ether is the most basic of the ethers and can be found in space. In fact, it's one among the most common chemicals found in interstellar space's star-forming regions. It has the chemical formula CH3OCH3 and comprises of two carbon atoms, six hydrogen atoms, and one oxygen atom.

These molecules are theorised to develop in cold star-forming regions before the stars form from the dense clouds of material that exist there. Simple molecules, such as carbon monoxide, are thought to adhere to dust grains and form ice layers, which then undergo reactions to form even more complicated molecules.

An asymmetrical crescent-shaped feature in the disc around IRS 48, a star 444 light-years away in the constellation of Ophiuchus, was discovered due to an asymmetrical crescent-shaped feature in the disc where larger dust particles concentrate, likely formed by another body between the feature and the star.

This so-called "dust trap" is a location where dust particles can clump together into larger and larger clumps, eventually forming comets, asteroids, and possibly even planets.

In a 2013 study, the dust trap's discovery was described in detail. Astronomers discovered that the dust trap is also rich in ices that contain complicated chemicals in a research published last year. Brunken and her colleagues used Chile's powerful Atacama Large Millimeter Submillimeter Array (ALMA) to investigate what they could find.

The star's energy causes ices to sublimate when it reaches the dust trap. You can detect the signature of the molecules present in the spectrum if you use a strong enough telescope.

Different molecules can produce dark (absorption) and bright (emission) features on the spectrum of light that reaches the telescope as they absorb and re-emit light.

ALMA observed emission patterns that were "highly consistent" with dimethyl ether, according to the researchers. They also detected methyl formate, a simple ester with the formula CH3OCHO that serves as a building block for organic compounds.

"The discovery of these bigger molecules in discs is quite fascinating. We were worried for a long that we wouldn't be able to see them "Alice Booth, an astronomer at Leiden University, agrees.

"What's more intriguing is that we now know these larger, more complicated chemicals are accessible to feed planets forming in the disc. This was previously unknown since these molecules are usually submerged behind the ice in most systems."

This discovery, together with the abundance of dimethyl ether in star-forming areas, shows that the chemical may also be common in protoplanetary discs. It also means that the whole interstellar path of these molecules, from star nurseries to planets, can be traced.

"We are ecstatic that we can now begin to track the complete journey of these complicated chemicals from the clouds that produce stars to planet-forming discs and comets," says Leiden Observatory astronomer Nienke van der Marel.

"With further observations, we might be able to acquire a better understanding of the formation of prebiotic molecules in our own Solar System."

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