Scientists have discovered traces of building blocks of life around a young star system located 400 light-years away, a finding that may help understand how living beings evolved on Earth.

This is the first ever detection of this prebiotic molecule towards solar-type protostars, the sort from which our solar system evolved, researchers said.

Astronomers harnessed the power of the Atacama Large Millimetre/submillimetre Array (ALMA) in Chile to detect the prebiotic complex organic molecule methyl isocyanate in the multiple star system IRAS 16293-2422.

"This family of organic molecules is involved in the synthesis of peptides and amino acids, which, in the form of proteins, are the biological basis for life as we know it," said Niels Ligterink, from the Leiden Observatory in the Netherlands.

ALMA's capabilities allowed both teams to observe the molecule at several different and characteristic wavelengths across the radio spectrum. They found the unique chemical fingerprints located in the warm, dense inner regions of the cocoon of dust and gas surrounding young stars in their earliest stages of evolution.

Each team identified and isolated the signatures of the complex organic molecule methyl isocyanate.
They then followed this up with computer chemical modelling and laboratory experiments to refine our understanding of the molecule's origin.

IRAS 16293-2422 is a multiple system of very young stars, around 400 light-years away in a large star-forming region called Rho Ophiuchi in the constellation of Ophiuchus.

The new results from ALMA show that methyl isocyanate gas surrounds each of these young stars. Earth and the other planets in our solar system formed from the material left over after the formation of the Sun.

Studying solar-type protostars can therefore open a window to the past for astronomers and allow them to observe conditions similar to those that led to the formation of our Solar System over 4.5 billion years ago.

"We are particularly excited about the result because these protostars are very similar to the Sun at the beginning of its lifetime, with the sort of conditions that are well suited for Earth-sized planets to form," said Rafael Martin- Domenech from the Centro de Astrobiologia in Spain.

"By finding prebiotic molecules in this study, we may now have another piece of the puzzle in understanding how life came about on our planet," said Martin-Domenech.

"Our laboratory experiments show that methyl isocyanate can indeed be produced on icy particles under very cold conditions that are similar to those in interstellar space," said Ligterink.

"This implies that this molecule - and thus the basis for peptide bonds - is indeed likely to be present near most new young solar-type stars," he said.